PSR-S keyboards use the lower end light touch keybed that most people can get along with but some hate it. It's the same as is fitted to the lower end PSRs. For info, the new SX model keybed is a longer travel and heavier weight version of this keybed.

Tyros / Genos use the FSX Keyned which is top notch in my opinion.

None of these keyboards are notably thin. I'd vote for a controller. Whilst never had a play with the Arturia models they talk a good talk!