I had a concern when buying the GXP, well... a couple of 'em. Anyway one was would the seats be hard to clean?

Well, had it two months, 2,500 miles and so far they haven't shown any soiling...

However, I'm sure that will happen... any experiences on what to do or not do?

When I picked up my '05 GXP, it had an "Kar Guard" package (that I didn't pay for!) that included paint and fabric protection. I went ahead and treated the ultra-suede areas anyway with a Scotch Guard product which is approved for suede. I figure it'* easier to protect the suede than clean it. I know this suede is supposed to be artificial, but I would imagine any cleaning product approved for suede would work fine.

I have a 2004 GXP and sprayed scotch guard on it the first week. Its about 14 months old now and the suede still looks great (mine has the tan suede)