What is MCH rotation like?

Hi guys!

I'm debating whether I shoud main a summoner or a machinist. The only problem is I've never played a machinist at high level. What is the rotation like and is it fun?
Last time I've played it, it was waiting for procs , and using ammos at the right time with the procs. Is it still the same? What are the weakness of MCH?

Managing heat gauge for most part.

Here: http://forum.square-enix.com/ffxiv/t...w-MCH-rotation