I finally bought an Apple TV 4K 32GB, probably just months before they will release a new model of course.

It took me nearly three years to talk myself into purchasing one, after all, they are rather pricey. Here is my somewhat brief review and random comments. I just got it yesterday afternoon, so I have limited experience with it so far. I do own an old Apple TV 3rd Generation which does not have the app store capability, and quite frankly it blows chunks. No comparison with the newest version the Apple TV 4K, so I will only compare the Apple TV 4K to Fire TVs and Rokus I own.
I’ve been mostly using my Fire TV (3rd Generation) and the Fire TV 4K stick, but mostly the 3rd gen as it seems to do better over all. While these are decent streaming devices, they are both short on internal storage at 8GB (with only 4.5GB available though). The 3rd gen has a bit more RAM at 2GB compared to the 4K stick's 1.5GB. Despite the mediocre specs, they perform fairly well, but they are not speed demons nor do they have enough internal storage to store enough apps. In this day an age when we cord cutters tend to install apps like Netflix, Hulu, Disney+, and a whole list of others, you can quickly fill up the internal storage. They both perform well as far as WiFi speed and are capable of delivering 200+ Mbips DL speed with my 200+ Mbips internet account. However, the ethernet connections are both clunky (requires a separate dongle) and slower as they max out below 100 Mbips due to the slower 10/100 capability. I prefer using ethernet when possible to free up WiFi for other devices, but I used WiFi with the Fire TVs since it provided twice as much DL speed. Even at that, they do tend to buffer a lot in some apps like Philo, at least on some channels. They also tend to close a few apps on occasion, so restarting some apps like Philo on a regular basis is a good practice. Over all they seem rather sluggish going from one app to another. I do love their ability to control and use my Fire TV Recast though, and it does a great job of recording OTA programming.
As for my Roku Ultra, well pretty much ditto for what I wrote about the Fire TVs I own. The Roku only gets about 85 Mbips DL speed on ethernet and 75 Mbips on WiFi though, but it has less buffering on average than the Fire TVs. I rarely use it though. It is a reliable option, probably a bit more reliable than the Fire TVs, but again the performance is decent at best.
So far my Apple TV 4K seems blazingly fast. (I only have an HD (1080p) TV, so all my comments are about HD and not 4K or HDR.) The ethernet yields 200+ Mbips of DL speed since it has gigabit ethernet. It has 3GB RAM, a fair amount more than either Fire TV. It definitely has way more storage at 32GB. It has a faster processor too. Let's face it, buying the Apple TV 4K costs way more than the Fire TVs and Rokus, but you are getting the streaming device equivalent of a Mercedes or Bently compared to a Chevy or Ford. You do get what you pay for! The Fire TVs and Rokus work well, but they are inexpensively designed to be affordable while providing an acceptable streaming experience. The Apple TV 4K is a premium priced streaming device that provides a better streaming experience, which you may or may not need.
So far I'm really impressed. The setup was quick and easy since I was allowed to use an iOS device to clone much of the process via iCloud. I love the fact that I can easily use my iPhone or iPad Control Center to type in search fields and enter account names and passwords. I can even use the Face ID or Touch ID on my iPhone or iPad to enter account information quickly. The video quality is very good, and so is the audio quality. Interfacing with my iThingies is great, and easy.
The remote, well it blows chunks.

But I knew it would. It was just as bad as the countless reviews said it would be, so I wasn't surprised by it being so bad. But I already have a Inteset IR learning remote and Apple was thoughtful enough to make programming an IR learning remote super easy and very fast. So within 5 minutes I had a good remote. The Apple remote will be used only for Siri. So what is bad about the Apple remote? That gosh awful trackpad that makes it way too easy to screw up and move the selection point. The trackpad is a mess. The remote is insanely thin, that seems to be an Apple thing. It is so thin and small that it literally hurts my arthritic hand to hold and use it. I recommend getting a good 3rd party remote. My Inteset was only $20, and it works well with 4 devices and is fairly easy to program.
The Apple TV interface was surprisingly simple and easy to use, as in easy to navigate to where I want to go. No clutter, and very little in your face advertising. I was very pleasantly surprised. It is also customizable so you can move your favorite apps up to the top rows, and delete the ones you don’t want. You can get into some really cluttered screens though, but you can easily avoid those if you want to. I just use the uncluttered Home screen most of the time. When you go into other screens to browse, you see alot of stuff from other services like Netflix, Hulu, etc., so just like the Fire TV you might think these shows are free but they cost (either through subscriptions or to purchase/rent). Again, I stay on the Home screen to avoid this as much as possible, and I tend to do my searching and browsing from within apps like Netflix, Hulu, etc. BTW, you can install Amazon's Prime Video app on the Apple TV 4K and watch your purchased or subscription shows/movies. That is a big plus since I have more purchased items from Amazon than I do from Apple. If you have Amazon add-on channels, you can watch those via the Amazon Prime Video app too, but not through separate apps. In other words, I purchased the Amazon add-on channel BritBox subscription. I can watch it on my Apple TV 4K via the Amazon Prime Video app, but I cannot watch it through the Apple TV 4K BritBox app. But that is okay with me. Had I purchased the subscription direct from BritBox owners then I could have used the Apple TV 4K app. I do have MotorTrend and Curiosity subscriptions purchased directly from the owners of those channels, and the Apple TV 4K apps are very nice for them. Netflix and Philo are both really great on the Apple TV 4K too.
So far I highly recommend the Apple TV 4K. It has a nice interface that is easy to navigate. It has excellent video and audio capability on HD, no clue about 4K and HDR as I don’t own a TV with those capabilities. It is well integrated with iOS and iPadOS. (I haven't tested with macOS yet.) The performance and reliability appear to be top notch, so far. I think it was definitely worth the premium price point in my case, but of course YMMV. I'm a cord cutter and don't have cable/satellite, so I need good and reliable streaming to watch TV shows and movies. It was worth a premium price to avoid the performance issues I sometimes encounter with the Fire TVs and Rokus.
Note: I haven't tested it with Siri yet, nor have I tested it with Apple Home devices. (I don't own any Apple Home devices.)