Just got off the phone with Casscades, sounds like JPW and Maravia pads are exactly same thing except the valves. They both get the foam from Salt Lake. I am waiting for a quote from Casscades to compare to JPW's pricing, would be interesting to see.
JPW told me he can put C-7 valves in per request at no extra cost. So basically both companies have the same pad. I've dealt with JPW customer support in the past and totally happy with them, at the same time I bought my boat (Maravia) from Casscades and service is awesome too. In my perspective, it just comes down to price. If interested, I will PM you the price comparison for the exact same pad.