That's a good question! I compared the May vs. Spring 3 vs. Terminator Plus at the same time. Going over my notes the things I see between the two Holos was:
The May and Spring 3 are pretty similar
- May has a larger soundstage
- May has better separation
- May has better focus (instruments / voices in space are highly defined, and not smeared in space)
- Bass is pretty close, and I couldn't discern much of a difference
- Treble extension and "airiness" was the same to me
- The "believability" of voices, and instruments was about the same to me. A couple of times I preferred the May on my reference tracks. But suppose it was pretty clear on 3/22 tracks. So, pretty close to the same.
Those were my observations. I'm a big fan of the May, and think it scales to the very highest setups. In fact, the T2 + SGL Sr setup is probably the most detailed money can buy (IMHO!). If the T+A is that good, I'll have to spend some time with one. Sounds exciting