I have never listened to or owned a preamp as exotic as your Amati but have had preamps from Hafler, PS Audio, Dynaco et al and have to say the Decware preamps are a different animal than those. Very dynamic and clear and you can add "color" with tube choices and gain structures. . . but you are not stuck with a "coloration" as I had been with those preamps.

I have both a ZTPRE and CSP3 (with Anniversary mods) and use both in my main system. Originally I used the CSP3 there to provide headphone amplification, but honestly. . . although either alone is good in the system, both in the signal chain is another fascinating opportunity to ride the gain and the resulting sounds are better than "just the one."

In another system I have a CSP2+ with the Anniversary mods and that is a fantastic preamp for the Taboo Mk IV there (and a DALAUDIO amp I am using currently) and a killer headphone amp for the Sennheiser HD800S I use there--that is one of the best headphone/amp combos I've every heard.

I would say if you want a preamp that "vanishes" the ZTPRE is a great unit. Though it does not have a tube rectification the rectification that Steve chose is "just right" imo and I don't miss rolling rectifiers there. The CSP3 is more of a "paintbrush" with signal tubes and gain adjustment--and you can make it appear very transparent and uncolored with the same approaches. If I were looking for another preamp and had a balanced source the ZTPRE would be a great pick (with either the optional RCA output or a ZBIT) and if you have an RCA output on the source the 25th Anniversary CSP3 would be a great preamp.

Hope that's helpful. It's no secret I am a big fan of Decware preamps.

Steve's first preamp model, the original ZTPRE:

https://www.decware.com/newsite/ztpre.htm

One of these came up for sale used once some time ago. I kick myself for not trying to get it! I think it's a fascinating product.