Used monitor under$600 with good bass low levels

Ejlif, Mapman, thanks for the recommendations, I am still curious as to what the ohms are like. I am hoping someone in nyc invites me over.
Have you(plural) had a look at the bolzanos.

Shadorne,
Close, you forgot skiis. They come with release bindings in case the doctors show up I can quickly dismount the craziness.
I plan on consulting with Meniscus, they have been in the business for a long time. I will let them help choose the drivers and design the cross-over and other parts.

Shadorne,
I should have mentioned it earlier I thought others realised I am prudent in my efforts and take the smarter route. But then looking at my tt I wonder what others think?
I assure you the suspension works, at the tt and the speakers.
I believe speaker companies should take that route in designing. Imagine every house has a different type of floor, some concrete some wooden and all have different densities. If speakers were designed and played back suspended there would be a consistency that the designer will know will be heard through out. For the exotic boutique speakers I would like to see the optimal room size recognized and for those with the megabucks who buy this to build accordingly.

So far so good.
Just got those jbl's suspended and even though they don't come close to the merlins they are giving that same effect as the bolzanos. Only thing it's way off in tonal balance, well not way off but certainly off. The treble is suffering. Exactly what I suspected. Next to do thing, discuss drivers and volume of cabinet and decide on cabinet material. I suspect since treble frequencies are more directional the tweeters will need to have greater decibel output. I am thinking in the beginning of biamping to have some control over tonal balance, since it will need to be tweeked.
Any suggestions?
I am thinking of using scanspeak revelators.
I like the idea of sat/sub, thanks Tweak1, I want to go in that direction but where should the cross-over be at? I was thinking of somewhere around 60hz? I would like to keep the workload low for the mid/woofer to lessen any intermodulation distortion.
Thanks for the help, I hope this works out, as I am listening now to my compromised system I like what I am hearing. I hope to get that high frequency energy that the mbl's have. It's sort of crisp bright life-like without edge or pain, at least to me. The esotars are excellent, if I can get them to work in this project that would be great.