I'm really impressed with them combined with the SRM-252S. I had no idea that little amp would sound so good. I like the 307's FAR better with the 252S than I did with the SRM-T1W (which I had for about a week and which sounded sort of dry/dull and etchy with the 307's).
The only other benchmark I have to compare the 307's with would be the SR-303's ... which I also really liked and which I think might have been just a bit more smooth sounding than the 307's ... but that's just distant memory talking and so who knows.