Me thinx it all bs, how can you exclude either one of them techniques when you're into electronic music or hiphop. Both can be quite demanding in terms of writing scores and arrangements and for both goes that the sound means everything.
In terms of sampling, a phrase can contain a score you intend to use, or you write a score based on a fragment of a sample which you handle as an instrument, instead of loop. You can consider it as being relativly easy to produce since in either form it was the sound that appealed to yo and made you use it, not much need for editing the sound itself ( if that's what you go for ). The other side is originality, thus investing time to make sample libraries and your approach as how to use them samples in a score. I also think, that in case of a good source for samples, you do not need to edit/master a lot around a track, considering the sampled recording has wennt through mastering already.
" keyboard beats " ( I have to be honest, I never liked the name ) to the criteria Afrique mentioned, is performance driven, in that all scores n sound come through by your editing because they're clean. The fact that midi scores tend to sound less warm is simply because of the instrument you're using. In no offense will a Triton sound as good as a b3 with rotary cabinet since there is no a rotary speaker in your setup ( the b3 sample sound better and warmer, hence it being the original b3 and don't forget the mic to record a rotary ).
All in all, to achieve a good natural warm sounding midi score/composition ( keyboard beat ) you'll depend on a lot more as oppossed to sampling. You define the sphere instead of a sample and to my opinion, it's what instrument you choose and how to process the signal through which piece of external gear that determines how well the sphere is going to come out or whatever purpose you're trying to achieve.
In that you need to know 2 things,
1. What make n model would give you the sound you want to hear.
2. How well can you composit a score, but that being rather relatif.