Yes, all vials of T say that they are for IM but can be injected subq. I am not sure there are any conclusive studies regarding subq being a more stable option than IM. The majority of guys I would say are on IM, with a smaller percentage that do subq, and an even smaller percentage that use some other means (gels/creams, pellets).
Personally, I do not see much of a difference. I know I'd never be able to inject in my stomach. I don't think I'd feel any better/worse using a smaller needle or going at a different angle in my thigh. Anxiety goes away with experience. It stops being something that you're apprehensive about and turns into that thing you have to do once a week.