Any monitors clearly better than Pulsars?

After some recent amp and preamp upgrades, I'm wondering if it's possible to push further on my speakers.

Right now, I'm running Joseph Audio Pulsars, which I enjoy thoroughly. Because I live in an apartment, floorstanders are out of the question, and I know the Pulsars are some of the best monitors around.

My question is: are there any monitors that are clearly head and shoulders above the Pulsars, which might be worth a listen? Budget-wise, I could probably go up to $12k used.

In terms of what I'm looking there, really there is nothing specific. I'd say the same about upgrading from the LS26 to the REF 5SE; I wasn't looking for anything specific there, but the 5SE is clearly better :)

That said, I'd be hoping to find a speaker that is clearly an upgrade. If any other monitor would be a minor step up, or more of a lateral move, then I'm happy standing pat with the Pulsars.
Having heard the Pulsars on several occasions I completely agree... very enjoyable. I was at Goldprint Audio a couple of weeks ago to listen to the new Alta Audio Celesta FRM-2's and ohhh mama! A very well balanced speaker with incredible bass (similar to the larger Perspectives) and a wonderful top end. I believe they're right around your stated price point and definitely worthy of an audition. Maybe give Taylor (Goldprint) a call since he's a dealer for Alta as well as Joseph. I'm sure he's had a chance to compare both and would be able to offer an honest opinion.