I use the Kobo Glo HD as my only reader now, and I upgraded to 4.3.8966 and I'm happy with it. One of my readers got the new home screen pushed with the upgrade, there's a chance yours might, but you can go back to the old home screen with GeoffR's patch. If you upgrade past this version, you will get the new home screen and there's no way to get rid of it.
Take a look at
this thread about the newest home screen (but I don't believe anyone posted any screenshots, so it's not very helpful if you want to see it first), and at
this thread, but note that there were some changes to it after this latter thread. You can see a few screenshots
here, but I'm not sure if that's the older version or newest version of the new home screen.
But 4.3.8966 works very well for me, nothing is broken, page turn speed is ok, I have no complaints at all and probably won't update further because of the new home screen (just my preference, you may like the new home screen). I think the biggest negative for you with the new home screen is not being able to have as many "open" books that you're reading at one time and having to hunt for them in the library.