I know this is apples to oranges but just a comment; I have four of the DB651 in my boat, they are excellent but I'm using them with a sub with crossover set fairly high to make up for their lack of bass. They are very "bright" speakers. I'm driving them with 125W and they don't care but I'm not running volume more than half and gains are set with DMM. I'm not sure how that brightmess would do on a bike. May be ok at speed.

I picked up all four for $139 at sonic

 

I'm looking for something to install on the inner fairing side walls of a Roadglide, I believe the Infinity's are too deep. I'll consider the specs, but the specs say nothing of reliability. It's a rider not a show bike, and it will get cold, and it will get wet, durability trumps all for me.

 

biketronics 7.1" fit fine in there. lifetime warranty.. hard to beat...

 

I had the DB651's in my bike and they sounded like crap and will quickly bust. But, a local shop here in Charlotte, that's all they use are DB651's. Go figure...