Brand-new iPhone 4 8GB (2 year warranty), stay at iOS6 or update to iOS7?

It's a 1 year Apple limited warranty, and 1 year provider limited warranty (repair service I'm guessing) = 2 years.

I know there's no way back after updating which is ridiculous, but it doesn't stop me from asking myself that question.

I heard about it being slower and people having Wi-Fi problems after update, but if it is something fixable by Apple, why not do it and have it fixed? Will the problem persist/reoccur?

Also, if I wait, is it possible that they can release a more iphone 4 friendly version of iOS7 (possibly with a switch in the settings to lower the dynamics of the graphical user interface)?

Added (1). Thanks for the reply so far! I forgot to mention: I know I would not update to iOS7 if I had no warranty, since its practically digging its own grave, but I do have a 2 year warranty, and some apps already say that I need iOS7:/ e.g. Dropbox and garage band. (which isn't that bad, but still).

Stay with iOS6, because it works much better with that phone. I updates my 4S to iOS7 and I've had nothing but problems! My battery life absolutely sucks, things run much slower, and it's just an overall pain. I regretted updating my phone just days after I decided to do it. Yes, the new update looks a lot nicer (in my opinion), but it will only mess with your phone. Trust me.

Also, I'm sure with all that brain power at Apple… They could very easily fix this problem. But do they want to? No Because then they are making less money. See, by putting out a cool new update… Everyone wants it.So, everyone gets it because it's free!) Then, when it doesn't work as well with the older phone, people want to upgrade to a newer phone which of course makes Apple money. It's definitely no coincidence that every new update works better with the newer phone that the older one!