The only way to be satisfied with the end result will be to try the amps in your own system and compare them directly with your BAT. I suggest you listen closely and objectively since, in my experience, the results may not be a night and day difference, but rather one or the other may be better at certain things. Be prepared for the Class D to be much quieter but I wouldn't get overly hung up on that benefit. Compare note development and soundstage between the two and listen for fatal (i.e., dealbreaker) type issues that you just cannot live with long term.
If you want to try NC1200, I think I know who to contact so you can audition a pair in your system. Some Class D amps you may need to actually purchase and then have a 30-day "return" period, with or without restocking fees. Small price to pay IMO to get what you want, or to not make a big mistake.
Since you are so curious, I suggest deciding how much you want to spend, and then asking the folks here for Class D amp suggestions in your price range and then contacting those manufacturers to try and set up an audition. BTW, they are mostly easy to ship and some come in flight cases which would make it very hard to damage them. It sounds like you are at the point where you need to hear some for yourself in your own system.
If you want to try NC1200, I think I know who to contact so you can audition a pair in your system. Some Class D amps you may need to actually purchase and then have a 30-day "return" period, with or without restocking fees. Small price to pay IMO to get what you want, or to not make a big mistake.
Since you are so curious, I suggest deciding how much you want to spend, and then asking the folks here for Class D amp suggestions in your price range and then contacting those manufacturers to try and set up an audition. BTW, they are mostly easy to ship and some come in flight cases which would make it very hard to damage them. It sounds like you are at the point where you need to hear some for yourself in your own system.