I have had the 350, 900 & 950 and am sad that Sony discontinued the 5 & 7 inch sizes. However, I read on my T1 more than my X50 models. Mostly because the T1 text clarity is fantastic compared to the 950. I really like the ability to change the font of your book in the menu system - very easy. The Amasis font is great. I also like being able to download books from the internet on the device, especially borrowing books from the library. It doesn't bother me that it's made from plastic. It is light. There are also many things you can do with it if you check out the developer's forum. You can install a modified homescreen with new features (kind of like PRS+ but not quite as featured). You can root it and add Android apps. I don't miss the 3G because I always am somewhere with Wi-fi. I took it to England last month and had no problem purchasing books and downloading my newspaper subscription.
What I don't like is that you have to sync with the new Reader for PC/Mac software which is far inferior to the old Reader for Library software. I gave up on that and started using calibre to manage my library. The other thing that the 950 does better is auto-delivery of newspapers. On the T1 you have to go to the Reader Store over wireless and tell it to download that day's edition. An extra annoying step! I hope they update the firmware soon. Also newspapers look better on the 950's 7 inch screen.
For me the Sony firmware is what I like about their ereaders compared to the other brands. So, if you have to get a T1 to replace your beloved 950 it's not the end of the world!
