I know one thing. Upgraditist can be contageous and you were recently exposed to it right here. Probably from eating a chunk of mushroom you found down here in the rabbit hole. Stay away from those and that crazy caterpillar and whatever it is he's smoking. You'll be spending money before you know it!
Man, I think you already know the answer. You gotta listen and hear for yourself (I get that one a lot too). I've only ever heard the 65's in a magnolia room and every speaker sounded like poop in that room... I will say I owned the SM55's and I did like them for the price. Despite the bad rap I think they still make some good speakers.
One thing I would say is, if you're gonna do it with upgrading in mind it's gonna cost more than a few bucks to significantly best the 65's imo.