I believe CMAC is as good as it gets when it comes to a venue in WNY. They bring in quality shows all summer, the acoustics are great, lots of parking available, choice of seating (reserved or GA), and plenty of food and drink options.
Of course there's room for improvement. Parking in a lot will set you back at least 45 minutes on your way home. This they should work on. Alternatively, tailgating in the lots is allowed; so those worried about over-priced food and drink can have their fun before the concert.
CMAC is definitely a larger headliner attraction. Parking is a biatch here. You gotta walk a ways to get to the venue unless you wanna shell out $20 for VIP parking and then have a difficult time getting out. It is 10 bucks for general parking. It is WAY better than Darien Lake's parking havoc though. Canandaigua gets pretty trafficky before the concerts, so give yourself lots of time.
Beers are $9 for a 24oz cup. I got a plate of Dinosaur BBQ for $10 and think it was worth it. They also sell kettle corn there.
The security is strict about hanging by the bars and fences if you have lawn seats. If you have lawn seats you can't see much. The sound quality is okay up close to the bar before the seat prices, but if you go too far up the hill you can't hear as well. You can't see much though. You are allowed to bring chairs.
I prefer going to places like Town Ballroom, Waterstreet, etc. but the nice thing is that it is way cooler outside at CMAC.