At what weight benched should I consider buying a bench shirt to push my hypertrophy further? 315?
None. A shirt is going to do very little if anything for bodybuilding purposes.
I agree with Jstreet, no need for a bench shirt for increased size. If you want to do the same basic idea of overload do rack presses and reverse band presses (or just forced reps) where the bands actually help you instead of make it harder. It is a lot like the shirt without the cost and pain in the ass factor of putting it on and off
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