I own JM Labs speakers, though I have never been a fan of the Electra 906 specifically. I am not at all surprised you preferred the Paradigms. The signature series stuff I have heard has been impressive. If it weren't for the (in the case of the Signature's at least) unjustified "mid-fi" rep Paradigm has, I think these would have a lot more buzz surrounding them (recent Stereophile cover notwithstanding).
Although, if you are willing to buy used, you have so many options. My first thought, since you are looking at monitors, is to stretch your budget and look for a good deal on Cremona Auditors. I have seen these not uncommonly for $2900 or less (with stands, which you WILL need). These will put you an entirely different class than the other speakers you mention. In the right room and with a good sub (specifically, a REL) they can easily hold their own against the $9000 plus Cremonas, at least in my opinion.
Although, if you are willing to buy used, you have so many options. My first thought, since you are looking at monitors, is to stretch your budget and look for a good deal on Cremona Auditors. I have seen these not uncommonly for $2900 or less (with stands, which you WILL need). These will put you an entirely different class than the other speakers you mention. In the right room and with a good sub (specifically, a REL) they can easily hold their own against the $9000 plus Cremonas, at least in my opinion.