I dunno about best (indeed, I have
no idea of "best -- how many zillions of loudspeakers have been marketed since the Magnificent Magnavox* of 1915?), but I can tell you empirically that the hk430 goes very well with the original Polk Audio Monitor Series. I'd choose the Monitor 7A (but any of 'em would be a good choice).
whatmore by
mhardy6647, on Flickr
polk_brochure_back_pg by
mhardy6647, on Flickr
I'll also repeat a popular internet factoid. Those of (
ahem) us who feel that pairing any of the Klipsch "heritage" speaker systems (e.g., Heresy, Cornwall, etc.) with solid state amplification is a flagrant violation of the Geneva Convention have taken note of multiple claims that the little hk430 is one solid state exception. I first read of the Klipsch Heritage/hk430 pairing in posts by a guy at the Klipsch forum who used to
build the classic Klipsch models.
*
Peter L. Jensen - Wikipedia