SAM is incredibly easy to pick up and play. However, the skill gap between a decent SAM and a great SAM is how good your ability is to forecast and execute the growth/spending of Kenki. No more so than when they hit level 70 and gain access to Guren.

Because of this, SAM can be extremely punishing to the player that (example): fails to plan and consistently has Guren sitting off cooldown - or decides that Kaiten would be better spent on Setsugekka than Higanbana during a boss fight. When DPS is the ONLY thing you bring to the table (aside a slashing debuff that WAR and NIN also have), you need to put up numbers to validate your existence.

SMN, I have no experience past 50 (yet). I've heard tell from that community that it has become much more about burst damage phases - and can be very punishing if you fail to line up your cooldowns and whatnot for those phases.

I think all jobs have the same issue. If you have poor resource management and spam buttons - you're going to have a bad day. If you're good at planning a few steps ahead of things - you should do great.

Please note, SAM is new. SMN has only had 2 weeks to process their changes. We need more time before the dust really settles.