If you restart your berry quite a lot (maybe 3 times a day most days because you install/remove apps) compared to someone that only does it when needed, whos will tend to last longer?
This is a hard question to answer due to every user is different and it is very hard to test. Everyone has different apps downloaded, different websites visited, etc that play into life expectancy of a device, so it is almost an unanswerable question. Only advice that I can give you is that you should only restart your device when it is required such as after upgrading of apps, you see some memory leak issues, etc.