It seems there are a few more differences between the 54 and the 9100. I am having trouble finding full specifications on the 9100, so some of this is carried over from the 1015 as well
The 9100 uses MCACC (similar to what's on the VSX-53tx), the 54 uses the Advanced MCACC, newer generation, more accurate, faster (similar to what's on elite 59, 56.)
The 9100 doesn't have audio/video lip-synch adjustment the 54 does. May be useful if you have HD.
Some slight difference in the cosmetics. I can't find anything about the bass management, but the vsx-1015 only allows crossover at 80 hz. The 54 has variable crossover 50,80,100,120.
The weights appear to be similar, so there doesn't appear to be any additional body stiffening.
The 9100 gets a backlit remote, (54 doesn't). Both units benefit from Air Studios tuning on the MCACC fiinal product.
Which feature do you get on the 9100 that you don't get on the 54? It appears that both have the same number of inputs - I would have thought the 9100 would add another video component in.
54 can be bought on-line for around 650, 9100 for around 500.
Interested to see where you go and how satisfied you are.
I have the 54 and I love it!
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