I'm on my 2nd pair of MKIII's purchased direct from HiVi/US office (it was between drops). Both pairs behaved/sounded the same. Reasons I sent back 1st pair had nothing to do w/sound or performance. Anyway, a few impressions that may help Solarium and/or other MassDrop readers "on the fence" about these speakers:
1 - They sound amazing. I'm a long-time audiophile, someone who chases the best possible sound, and IMO, these are it on the desktop. Perhaps not the ultimate in razor-sharp detail, power, flash 'n' sizzle (spend thousands on Genelec or other studio monitors for that)--but for listening to music, these really are it.
2 - They play very loudly when pushed. If you're worrying about the volume the dedicated amps can generate, either you listen to such loud music that you risk deafness; already have some deafness; or just listen to extremely loud genres of music for which speakers like this may not be the best choice anyway (ie, the nuance & delicacy they're capable of is less evident at high dBLs on music like techno, heavy metal, etc--though these babies definitely can rock out).
-- A word about the bass. There is a LOT of bass coming out of these speakers, no doubt the result of dedicated amplification + large speaker size. I probably should get them further out from the backwall (difficult in my situation) to see if bass thins out, but I just love the fullness, depth & clarity of their bass. They hit very hard in the bass/mid-bass, considering the fact they also play with considerable finesse up above.
3 - I've heard zero hiss--and I do mean ZERO hiss--from either pair, at any volume. I'm in a home office 12+ hrs/day, just 2 ft from the speakers. If you're getting hiss, my advice is to make/remake all connections; do some testing re components you connect to these speakers; and change the wire that connects sound card to Swans (in no particular order). FYI, I don't use my PC's soundcard at all*: I use a good quality USB-connected DAC (Peachtree Audio's DAC iTx) running through a passive volume controller, then on to the Swans + sub. I'll soon be significantly upgrading the PVC & sub and adding an external crossover.
*I did use soundcard for awhile only as a source of optical/toslink signal to a different DAC, 4-5 years ago when I had different speakers.
4 - The adjustments on the front of the powered MKIII speaker (right) really do adjust the sound. Slight upward/downward adjustments of treble or bass controls are readily audible. IMO flat works quite well w/these speakers, but adjustment is definitely possible/effective if needed.