I think one person had an ASA o-ring break, so I wouldn't worry about that.
Most threads I see that have anything to do with dropoff are in the extremely early stages (like first 1000 shots) while things break in a little.
Do yourself a favor and read some of the threads about the GT in here and you will see plenty of our opinions on it in great detail.
Honestly you are not going to find many people in here that are going to tell you not to buy one, as most of us are MacDev fanboys, myself included.
I love my GT to death...just returned from playing and it shot incredible, which you will get accustomed to with the GT