Thanks everyone for your input. Scrappy, thanks for the offer on those RB-25's. So, my BEST option would be to go with those and pair them with a RP-250 or an RC series(RC-52 RC-25 or similar) it looks like. Those 25's can be wall mounted right. I have 2 little ones that would constantly be playing with them if not.
If I have to settle for cheapest way to improve what's your thoughts about the synergy C-2 or C-20. It would be an increase from .75 to 1" tweeter and 3.5" to 5.25" on the midrange and 75/300W to 100/400W on the power. Those both look like they'd be an improvement over the quintet center I have now and look to be pretty compatible. I suggested those because I see a lot of them available. What would be the max I should pay and what's the difference between those two? How about any good places to shop on line for used other than ebay?