Not to go against the grain but T3 should be used with moderation.
Ramping up to doses of 200mcg per day, and using it for extended periods of time, can permanently shut down your thyroid gland.
Imagine being permanently depressed, eating 1200 calories per day and not losing any weight, having the chills and episodes of extreme sweating and there is no cure for it.
Unlike the testes, the thyroid gland does not always bounce back. You'll be stuck having to take it every day, for the rest of your life.
How do I know? Because it happened to me.
IMO unless you are pro bodybuilder, I would stick with OTC supplements and focus on diet and training. Losing an additional 5-10 pounds with T3 is not worth it.