how do maggies sound with b&k st-140 amps?

There are many models to choose from under $1000.00.
I think any of the ones you have mentioned will work just fine with your amp and room size. I doubt you will feel the need to bi amp those models.Some of which cannot be bi amped without some modifications. Try out some MMGs ($550.00) and a Panny XR 25/45 ($300.00) both can be returned so you have nothing to lose. The combo will put you at roughly $900.00 with shipping and you get a decent tuner as well! This will save space and give you some seriously sweet sound for little money. I guarantee you will be scratching your head trying to figure out how something so inexpensive can sound so good.
Also with the left over money you can pick up a Adire Rava($400.00) sealed sub and be in heaven! All you need to add is a cd/dvd player as a transport. That will leave $300 for cds,cables ..etc.
Happy Hunting!

Highs a little on the weakside?? HuH!!
Loonton I take it you haven't heard Maggies with the True Ribbon tweeters! I am talking 40 KHz extention..just how high do you need it? Bass isn't thumping on Maggies but it is very articulate and well defined.

I hear ya Eldartford ...I have mine padded down with 2 ohm resistors.It would be too much of a good thing for me as well LOL!!! I like the extention but it must be kept under control. I noticed things really opened up after bypassing the fuse and metallic sounding steal attenuator. Also replaced the stock resistors.Transparency in spades now.
I listened to Medeski Martin and Wood the other night I could actually zero in on a conversation going on in the background...while the band played.Never even heard this before on the this recording..next step maybe some new inductors and other crossover parts.