Accuphase class A amps - going up the food chain from an A-48 to an A-80 or A-300?

Earlier this year I acquired Accuphase separates (C-2450 pre-amp, A-48 amp) and have been very happy with them.  

We have a decent resale market in Canada for Accuphase products, and I was able to snag a C-2900 pre-amp at a good price this past weekend.   We see mostly integrated amps on the resale market here, and current production separates are much harder to find.

The C-2900 sounds noticeably better than the C-2450, and it got me thinking about moving up from the "entry level" A-48 to either the mid-level A-80 or even the top of the line A-300 monoblocks (though size and expense are almost prohibitive).

Does anyone have any experience or advice about moving up from the A-48 to the A-80 or A-300 monoblocks?

BTW Accuphase pricing in Canada is significantly better than in the US - so much so that Canadian Accuphase dealers are not allowed to post prices online for fear of alerting US customers to how unfair pricing is in the US - and Canadian dealers are not allowed to ship to US customers.