I just purchased one of these last night after specifically asking for the standard model. The model with the performance center is the Model A1 Style Comp version of the M&P15-22. In addition to having the Laney Match Chamber, it also has a A1-Style Compensator, which some of the models do not have. I have to say I was quite pissed off when I read that you can't use the CCI stingers in this model. The fact that the guy at the gun store not only sold me the wrong model but also sold me some stingers along with it has me a bit upset. The Laney Match Chamber in this model is going to give you better accuracy but less reliability according to my friend who is a gun expert. I am still undecided as to if I am going to keep this model or return it for the standard model. Here is the A1 model: Product: Model M&P15-22 - A1 Style Comp