He has remained invisible for up to eight hours but has never pushed it further. For intangibility, he can only do his whole body for a few moments, but can keep a limb intangible for long enough to grab something and bring it to him. 
The jist I was trying to go for was that he has never pushed his powers past what he knows he can do because he has no desire to. I should've made that clear in his CS. I'm gonna add a relavent paragraph to his personality at that actually.