Yeah, Minnetonka Petco is good, just not a whole lot to look at. Crappy coral displays and unimpressive selection. But it's definitely better than your average Petco. Still, I wouldn't exactly call it a destination LFS. New Wave definitely is though.
If you don't mind driving 30 minutes out of MPLS you can also head over to Hudson and check out Acan Lord. I love that shop and the gentleman that runs it is a great guy. If you have time, it's worth the drive.