No stains that I can see and I wipe my packs down with a damp rag after getting home from each trip to keep them in the best shape I can.
I can't find any fraying threads or anything like that.
The only issue I can find with the pack is the sheath of the main drawcord is starting to fray a bit. It's not anywhere near being a concern right now.
I'll try to get some pics tonight.
ETA: Got some pics.