Hay Liam,
Bracing can help protect a joint during competition or high impact/velocity situations, however I would recommend ONLY using it for these situations. If you are in the gym etc. work without it. The reason being you want your local support systems to have to work to stabilize your joint. If you constantly use a brace to do their job, they will waste away and leave you in a worse position.

By the way, those exercises and stretches etc. we talked about earlier, continue them at least 4 weeks into not feeling the injury any more, and always keep good shoulder position when working out etc. or you will likely repeat the same injury. The hardest thing to do in rehab is to keep the ideals/exercises going after all symptoms have disappeared but it is necessary.

Let us know how it goes!

Regards,
Musculoman.

Edit: Sorry didn't see you said "Posture" Brace, similar thing though, people become too reliant on posture braces and they end up in a bad place. Continue your exercises and shoulder stability work, be aware of your posture and not letting that shoulder draw forward too much.