SST Ampzilla 2000 v2 vs Son of Ampzilla II


Looking for something new to drive my Dunlavy SC-IVas and am considering SST's Ampzilla offerings. My preamp is an ARC SP3. Hoping someone with a bit more exposure to them could share what they'd consider the pros and cons of each to be and whether the 2000 monoblocks are worth the extra money.
counterreset
GAS offered a transformer for bridging the original Ampzilla and the Son. 600wpc and 240wpc, respectively. Into 8 ohms, of course! 
Apparently there were two versions of the SST Ampzilla. V1 and V2. The latter used the same input stage as the Son mono amps.
I just see a biamp option on the back of the new 2000 v2.

@jackd thanks for the heads up. I reached out to him and it looks like I could get better bang for my buck trade wise on a pair of Ampzilla 2000s than for the SOA2. The holidays are making it tougher to find the extra $$$ 😅.

https://static1.squarespace.com/static/5480969de4b0f0d437dda5d4/5697d38fbfe873ec75c280d7/5697d38fbfe873ec75c280d6/1425429391702/amp2000-back.jpg
I ended up getting the Son of Ampzilla II from Underwood, but there is a faint buzzing. It is on both channels regardless of what preamp or input source. :-(