iPhone 4 bars drop

Hey everyone,

my iPhone 4 has already been exchanged twice since I bought it. The first time the upper volume button was broken and the second time it had a pixel issue.

Now I have problems with the home button. It doesn't alway react. The well known "antennagate" is also my problem. If I hold my iPhone in the left hand, it drops two bars and the 3G network gets worse.

I'm really tired of having problems with my iPhones. Last year, before I got my iPhone 4, I had the 3Gs and it also had so many problems.

So my question is: Should I just go to the Apple Store and do an exchange? Would they maybe exchange it with an 4s? Because it hasn't anymore these connection problems ("antennagate")? I'm really like desperate. I really love my iPhone but I ALWAYS have/had some problems...