I'm thinking on getting the new Nexus 7 tablet from google, but I have serious doubts about its long-term usability.

I have a crappy huawei u-8650 that in less than a year is almost useless (Long loads, slow response, I can't barely use it even to make phone calls, and don't make me talk about the battery) and I have seen some similar behavior in different android powered devices, so I'm a bit worried about that "programmed obsolescence" thing. I don't want to spend 200$ in a device today just to see that in two years it can't even browse the internet, either for the OS not being updated or for the hardware malfunctioning just in time for the new tablet model announcement.

So, do I have to worry about this kind of thing? Is reinstalling the original rom (Or an alternate one, I'm not only thinking on cyanogen but the Ubuntu distro for android, which seems to kick ass) a good way to keep the device healthy in the same way a format is a way to keep your computer in good shape and avoid slowdowns? Is the hardware really made to last?

Maybe I should take this question to the nexus 7 subreddit, but I thought that here would fit better, as I'm trying to aim to a broader topic (Not only this particular device, but any "old" android device).