Keep in mind that riding in the group will minimize the air resistance, so by only pushing a little bit harder, you should be able to make up those 3 mph easier than you think. Also, being in the group gives you a group mentality that should help give you that power boost. Group rides are really fun, just go out and join, do your part, and if it is too much for you, drop off the back and rest yourself. There is nothing negative that could come from it. BTW, I ride an Allez and I love it as an entry level road bike, but if the geometry is really as similar as RollCNY says, then maybe you'd be better off getting a different bike. You could always try the Secteur if you wanted to stay with Specialized, and it's a little more comfortable than the Allez for around the same price.