It is somewhat hard to get off, but I think only because the IS is kinda soft so the rubber support of the case kinda sticks to it. The IS is still in good shape though. I'm going to try to avoid removing the case too much. I think it would be best to smooth down the rubber support though to fit with screen protectors, but I don't know if I will.
So I'm not the only one worried about removing this case to clean the phone? I work in an office at a custom cabinet company and I did get a lot of fine sawdust collected in some areas of my previous slider cases. Hopefully it won't be an issue to remove this case once a week for a good clean.