The m650 by JL are rated 75w rms, you looked at the MX series not the M series. you'll want 100 to 125w put to the M series to be perfect... If your putting these 6.5" speakers in a boat, this is one of the times where you WANT marine speakers for sure... The alpine you spoke of will not have a continuos mid like the JL or WS speaker with the grill mount . So a minor offset most won't notice anyways.. but if you've heard them and like them, it's your call brother.... For the price of those, I'd still recommend JL or WS... but again it's your money and preference