I've been playing a lot of NL 50 full lately and previously played NL 25 6-max.

NL full is much more limpy PF and passive on the flop.

6-max is more tight-aggressive PF. Harder to know the players hand strength, but easy to feel the players out cuz there are less of them. Seems like 6-max is much more about outplaying the opponent and stealing many small pots.

Full I seem to get paid off more regularly with hands like 33 that I call a PF raise with and flop something like K3A.

Full seems much less volatile than 6max. I'm new to full though as I always used to play 6max. Only logged probably 20 hours at full NL this whole year. (Tons of full limit though)