Engine dyno vs chassis dyno

After working with Mustang Dyno, and the grossly over priced maintenance parts (bot dyno and 5 gas analyzer) I'd go engine next time for the R&D we were doing, but it all depends on your business. Do you build Cars or Engines? They both have there place, strengths and weaknesses. I'd personally like an engine dyno just for cam/engine break in and basic tuning.