look at the krks -- they are pretty universally praised and are in the $400-600 range. you should probably be looking at something with at least a 5" woofer. i can't find the specs for the ms 10, but the ms-20s are 3 5/8" -- way too small to get the bass you're looking for. here's a link to guitar center (a good reference point, price-wise) with the selection: www.guitarcenter.com/Search/Default.aspx be aware that anything under $300 is probably a price for EACH speaker...

I was on a hunt for mid priced monitors and tested out the krk rockit 8's, mackie mr8's, and the Yamaha HS80M's and I ended up going for the Yamahas.
Out of all of those they seemed to have the most crisp, detailed high end and nice low bass response. The krk's have a bit of a non pleasing mid range harshness to them while the Mackie's just sounded kind of muddy.
For the price range , I highly recommend the yamahs.
www.zzounds.com/item--YAMHS80M

...And yes, of course there are the Adam's, Genelec's, Dynaudio's, etc. But those are all higher price bracket monitors. Even the smallest ones.
From what I've researched, the Adams and their ribbon tweater technology are supposed to sound superior to the Highly praised Genelec's.
Actually there is a lower price bracket pair of smaller Adam's that I tested a while back and although they did have excelent crystal clear highs, they had almost no bass response. So I think larger ones would be the way to go. But you'd be spending upwards of 3000 dollars as well.