I certainly won't argue that the Monitor line is as good as the Studios. However, for the money they are great speakers. I like mine just fine.

Smooth2222, if you're happy to go with bookshelf speakers, then I'd say go for those. If you want some floorstanders, you're gonna have to fork out much more than you've listed. If you wait and try to accumulate a complete system of Studios on the used market, for a fair price, I think you'll be waiting a long time.
I compared Polk Audio RTiA7's with my Monitor 9's, side-by-side, in my own Rec room. My wife and I took turns blind listening to each pair and the 9's won it. The Polks cost about 50% more. So, there is value to be had in the Monitor series.
Best way to do this - compare a Studio 20 system with a Monitor system at your dealer. Only YOU can decide what's best for you. Despite what some of the other posters are saying, for the money, the Monitor line is perfectly fine. One thing to keep in mind - speaker sensitivity. The Monitor 11's are much more sensitive than the Studio 20's. Don't know how much you know about such things, but the more sensitive the speaker, the less power it will demand from the amplifier. That may or may not be be a major factor - depends on how big your room is, how loud you like to listen and the quality of your receiver/amplifier. Just another thing to consider...