I feel the AHB2 is somewhat "overpriced", in that u can now get really amazing class D purifi amps for half the price (and less). unless of course the intention is to buy into neutrality and a solid company with good reputation.
also, I also feel the Ferrum stack is a bit overhyped. yes, it is good for what it is, but what it is is a sub 2k amp hooked up to a nice power supply. don't get me wrong, I do like my ferrum stack and it serves its purpose ie quick no frills listen, sounds good, clean, and not needing to wait for tubes to warm up etc. but what it isn't, is end game, especially when susvara is the headphone. it does colour the sound somewhat and on that note if I was going for coloured and musical, I actually enjoy the Milo Reference more than the ferrum stack.
as usual, above are my opinions, for what it's worth and ymmv.
also, I also feel the Ferrum stack is a bit overhyped. yes, it is good for what it is, but what it is is a sub 2k amp hooked up to a nice power supply. don't get me wrong, I do like my ferrum stack and it serves its purpose ie quick no frills listen, sounds good, clean, and not needing to wait for tubes to warm up etc. but what it isn't, is end game, especially when susvara is the headphone. it does colour the sound somewhat and on that note if I was going for coloured and musical, I actually enjoy the Milo Reference more than the ferrum stack.
as usual, above are my opinions, for what it's worth and ymmv.