Hi Fplanner2010 & Knghifi,
When I had my Andra 2's I actually tried 300.1's, you can refer back threw past threads but in the end it just didn't do it for me, since then I have heard a couple of set-ups and below are some of my thoughts for what they are worth.
1. With my Andra 2's, one single amp just wasn't doing it for me, two was better but still did not have me wanting to drop the coin. The set-up most likely was not ideal, I had a ARC REF3 and VTL 7.5 original pre paired up, you can read my comments in relation to getting my VAC Sig. MK2a pre. I really still don't believe even with the pre-amp change would have changed my thoughts to the point of not looking for the ultimate amp.
2. A friend of a friend went from one to two and from the comments I came away with was that there was an improvement over all.
Fplanner2010 you have first hand expearience so you know.
I haven't read nor has anyone conveyed to me it was a night and day change, jaw dropping exsperience. I read allot mentioning better base, more contol, sound seems more at ease, images more stable etc.
3. One set-up I heard the owner was nice enough to do an actual demo for me, demonstrated the comparisons from using one to two amps, he was actually selling the 300.1's and I was again looking at possibly purchasing but in the end didn't.
I could most defiantly hear a difference but I would say in relation to what I mainly mention above.
4. The 450's, well what can I say that I haven't already mentioned above.
Never never never never have I ever heard anything like this ever, it's a jaw dropping experience leaving you in awe, well that was paired up with MBL's any ways.
I have personally owned allot of world class amps both tube, solid state and hybred along with demoeing numerous in my own set-up along with hearing in others places.
Some WORLD CLASS tube amps I personally owned; Audio Research 610T's, Ref600 MK2's, VTL Ref750's, Cat JL3 Sig., MK2 just to name a few.
Solid state; Bryston Squared 28's that I currently own, Bat 600SE, Krell numerous, Levinson numerous, MBL 9008 and 9001's, Boulder 2000 series stereo and mono blocks, Rowland, DartZeel, and I can go on and on.
All I can say is I wish these really weren't so friggen AMAZING! they are very expensive and the price just keeps going up, $78K now. I would have easily just left knowing they were better but oh no that wasn't possible they had to be absolute JAW dropping!
Others whom know me or have heard my set-ups know that I just say it the way it is, be it good or bad. I had allot of those components mentioned above in another set-up, speakers were Avalon Isis. I owned those for almost three years, I've always had two set-ups.
BEST of LUCK!