I think you nailed the 6505 the most, but to be honest, the JSX part doesn't do justice to what I think is a great amp.
Well they all use the same cab and mic position. The JSX has quite allot more MIDS tuned on the amp and still it has less mids then the rest of the amps. I still think the JSX could work well with the 6505 which has allot of mids