Most static raid groups raid 3 days a week a 3 hours, some do more, some do less. However, if you're using pf, you can always leave after an hour. 45-60 min is not very much though, getting a full group through pf and getting in enough progression with it in that time to eventually clear, I think that's highly doubtful. But each person learns with a different pace, if you're a fast learner, you might be able to pull it off. If you want to do the end game raids you want to thoroughly learn the fights. In the end you'll have to try and see if that is possible for you with your limited playtime.