I did the Marriott challenge last year, just to check it out.

To be honest, I saw NO difference between being a Marriott nobody and a Diamond. Except the occasional free (small) coffee or snack. My stays varied from Courtyard to Gaylord.

I am gold with Club Carlson and IHG. The former has treated me pretty well (upgrades, welcome gift) no lounge, no free breakfast. The latter has treated me as indifferent. Plus I find their properties underwhelming on the higher end.

Accor is nice too but don't expect too much from them. As Platinum, I have received slight to nothing in room upgrades. Capped free internet or throttled and no free breakfast at full service brands.

Trust me..the grass is not always greener. I would think SPG would be a great fit for me..however I stay in some small towns and while I can almost always find a Hampton, a 4 points is harder to find.