Smaller T's are a bit harder to take care of and more delicate IMO. And some are slow growers so they might be small for some time.

So would buying a 1/2" be the same as buying a 2", obviously other than size?
Not really.

See above statement. Also:

A 1/2" one will need it's vial lightly misted on one side to drink or you will need an eye dropper to drop a droplet of water in there so they can drink. You will need to rip a leg or cut a cricket in pieces to feed or use flightless fruit flies. You will need a super small container to keep it in, usually a clear vial.

A 2" one will be more hardy. You can use something for a small shallow water bowel. You can just toss a cricket in there for them to eat. You can use an appropriate size container. A mini or small kritter keeper, a plastic tub or whatever depending on what you get.