Before anyone gets going on this I'd like to point out that Emma has received an upgrade to the crossover and improved internal damping since she made her long, strange trip which began last winter. The result is tighter bass, more detailed mid-range and improved off-axis response.
Well I can give you my impressions of the Emma in a week or so. Between the Polk and the Klipsch, I would definately go for the Klipsch. I just remember comparing the Polk RTi series bookshelves with the LSi series at one point, and thinking just how worth it it would be to skip the RTi and go straight for the LSi, so night and day was the difference. As far as the RF-82 goes though, it is a completely different animal from either the Polk speaker or the Emma. Its efficiency, dynamics, and range are hard to match up with. Combine this with respectable accuracy, solid build quality, etc, and it quickly becomes the speaker I want for my HT someday. The Emma on the other hand I think will be perfectly suited for my bedroom, where its relative inefficiency won't be a major handicap, and its smaller size will be a major benefit. However, as I said, I'll give my impressions of it in a week or so. I've got high hopes for it either way.
If those are your three choices, you need to decide exactly what you want to hear. I would consider each of these speakers to be substantially different than the other two. What is it you are expecting to hear?