New APs improvements over older APs

[bob_williamson]

I realize the below is kind of a wide open question. I am looking for more of a wide answer and possibly some tips on what to look for in the statistics which may help figuring out the hiccups.

I am curious what makes some APs work better than others.

One example is our use of Apple TVs (not wired to the network). OS/x streaming full video from youtube and airplaying it to the AppleTV. In all of the tests, the laptop and Apple TV were connected to the same AP at a 99% connection, 5 ghz, 20 mhz channelization and all were placed in the same location/orientation. Results were something like this:
7363 some hiccups
7962 did not seem to be much of an improvement
7372 about the same
7982 no problems, minor blips. Significantly better.

I know that new hardware means new technology etc., but given the 99% connection in all cases it seems odd that there is such a clear difference with the 7982 especially compared to the 7962.

Is it simply that the CPU in the 7982 can keep up better than the others?

Thanks
Bob

Note: We just ordered a number of R700s which should be roughly equivalent to the 7982