I've owned and enjoyed the B60 for over six years. As good an integrated amp as it is, it's an even better preamp - in fact highly acclaimed given its price- and also a good class A headphone amp to boot ('phones driven directly from line stage up to 1W). Thus a B60 may be a better long term investment since you can not only enjoy it now but pick up a high end used power amp down the road. The fact that it has a 20 year transferrable warranty doesn't hurt either.
For several years now I've enjoyed listening to the Sennheiser HD580 and HD600 headphones through the B60's headphone amp. Digital front ends are a Linn Ikemi for redbook CD and (just recently) a Sony DVP-s9000es (soon to be modded) for SACD, Cardas cross interconnects and - by far the weakest link in my system - B&W DM603 tower speakers.
The B60 drives my speakers to acceptable levels in my ~16-25 foot listening room, though the amp does seem to run on the hot side , which doesn't me any concern.
Based on both headphone listening (using Shure E4C and the two Sennheisers) and on speaker sound from the B&W using the two digital players mentioned, as well as a Rega Planet CD player, VPI HW-19jr turntable, and once in a *great* while an iPod, I would characterize the B60's as being a fairly 'neutral' and resolving of fine detail in the midbass to mid treble, reasonably well extended in the upper treble though possible wanting in "air" compared to say, a good headphone amp, decently weighty bass but not if "slam" is one of your top priorities, a tad on the lean side and not especially well resolved down deep. However this is surely a limitation of my speakers, as bass heard in the HD600's is magnificently resolved, quick, and vivid. Then again, that probably stems from the B60 having such a good preamp which as you probably already know, can be decoupled from the less-inspiring power amp by f simply unplugging the external jumpers. By the way, my tastes is mainly for classical and bluenote era jazz (my reasons for owning audiophile gear) and some classic rock .
All in all, I regard the B60 as one of the more satisfying audio purchases I've made in recent years - great sounding and solidly built yet physically unimposing. Capable of resolving so well that whenever something seems sonically awry, I come to intuit that it's not the B60's that's causing something to sound closed-in or constricted, but something else such as my Cardas Cross rolling off the highs or pushing the upper mids forwardt.
I heartily recommend the b60, especially at the current used prices.
