Sampling on AR MMKII is apparently similar to DT, mono, 30 sec max. Very limited compared to OT (8m28s max, stereo). Playback too (64MB RAM. vs 85.5 MB + reading from 64 GB CF Card for OT, up to 2GB files per track, around 3h30mn).
Check that thread concerning DT vs OT.
Octatrack or Digitakt - no computer setup