Moshi is out with new Ivisor pro, I think they would solve that rainbow effect. Not sure though
But I've tried the skinmate matte ones and trust me, no rainbow effects. 100% satisfied

I just got it from bro Xavier a few days back and I think it's great for carrying the mbp itself and some additional cables like iPhone sync cable, the Mac alluminium remote .
I wouldn't recommend washing it if it's not really stained, try brushing it with a lint brush(it will be like new). Those red color brush u use to brush off dust n lint from ur clothes.
If really got stain, use a damp cloth to clean it. U can add some suede cleaner if u want
Only downside is that u can't really fit the MagSafe in the secondary storage
Imo, it's very high quality and feels good in the hands but catches lint way too fast cause of the full microfiber(terahedron) exterior.