Need a new power amp: Herron vs. Classe/Spectron

I have some very current-demanding 4-0hm speakers derived from Reimer Tetons. The only thing original are the cabinets and the ribbon tweeter; there is a single 7" Focal Audiom Neoglass mid and (2) 12" JBL woofers (can't remember the driver number) per speaker.

I'm using a pair of Herron M-150 monoblocks to drive them right now and am in the process of picking up a Herron VTSP-2 preamp, replacing a Dehavilland Ultraverve 2 with upgraded tubes. The M-150s do a tremendous job on my speakers in all ways except one: when the volume gets loud, they don't have the current output necessary to put out the low frequencies/manage the (2) large woofers. I put my sub amp on them just as an experiment, a Phonic amp that puts out a bunch of juice and 1100 watts/ch into 4 ohms; it pumped out the bass like nobody's business but otherwise sounded like you know what.

I have never listened to any Classe or Spectron equipment but have read as much as I could find on the web. The particular model of Classe I am interested in (that I can afford) is the CA-400. The Spectron of interest would be the Musician III Mk 2, of which there are good deals to be had right now. How would either of these two amps compare to the Herrons? I esp. like the ease of presentation the Herrons have, their liquidity and slight bit of lushness in the mids and highs, and their delicacy, such as with strings. Will either of the two amps listed give me these characteristics plus the additional slam in the bass I'm looking for? Thanks.

Bill