WAF = Wife (spouse, significant other) Acceptance Factor. The aesthetics police
I'm a big fan of the
Behringer B2030P that Bored suggested and have 3 of them as left, right, and center in my home office. They were designed for use at arms length and I'm just not sure that the have the ooooph for a large room like that before getting shrill. I just haven't tried it yet and they might do the job just fine. I just can't say for sure. But as long as you are within 10-12 feet they should be fine for sure. I can tell you that up close they rock! The downside may be a low WAF rating. With no grill covers they are a bit industrial looking. Hey, they were intended for recording studios not living rooms.
The same gentleman that turned us all on to the Behringers recently
praised the Infinity Primus P362 towers (~$200ea) and he's not somebody I'm about to argue with. I haven't heard them but based on who praised them I'd run to a store to at least audition them if I were in the market for $200 towers. The timber matched PC350 center is about the same price so we're $100 over budget (with the center) and don't have a sub yet.
The reason that I asked about room size is it's important in sizing a subwoofer. Assuming 9' ceilings (3900 cubic feet) Bored's suggestion should just about do the job. In my opinion any more cubic feet will call for a more powerful sub.
Regarding your question about auditioning environments. Most decent consumer priced receivers add or subtract nothing to/from the sound by themselves. But they may feature processing that adds or subtracts. That's why the first thing that I do is turn off any processing and set the tone controls to flat. Now we have a fairly even playing field. The second tool they sometimes use to steer you to a model is speaker volume. The one playing slightly louder will usually sound a bit better even if it's not the better speaker. If you can do A-B tests at as close to the same volume as possible it helps but that's not always doable. Finally bring your own CDs. Music that you know inside and out to test with. If you read some of the
pro reviews (reviews not "first looks") you'll get some ideas about what to listen for and then apply your own tastes.
As far as receivers go establish how much power your speakers will need and then select a receiver that can supply those requirements and has the features that you need. Just keep in mind that some companies are a bit "optimistic" when they rate receiver power and that differences of 10w are all but inaudible. You have to double output power to gain 3db of volume. Anyway in my experience Pioneer is one of those that get a bit optimistic. For most people an Onkyo TX-SR607 or 707 will supply all the features that they want. These regularly go on sale or can be bought refurbished from Accessories For less. I bought my bedroom receiver from them.