I would like to add to what Rikki wrote that both Korg and Roland give you the ability to edit individual percussions within a drumkit. This means, for example, that you can change the brush sound that corresponds to E1 until it matches the sound on the PA-800.
This is part of a general philosophy common to all Yamaha arrangers, kind of "take it the way it is, since we did already the job for you". Only problem with that approach is that, if you are not satisfied with what you've got, you have little chance to modify it.
I guess that it's for this approach that many people consider the Yamaha aimed to the home market, which -as we know- is composed mainly of people who want just to sit down at their keyboard and play, without having to worry too much about details like editing a drumkit.