I have both. One bathroom has 1/2" starphire the other is 3/8" I like the heft of the 1/2" even though it is not necessary (like HP in a car, after a certain minimum it really does not matter except to the owner). Hinges are designed to hold 1/2" and your designer should be able to pick the right ones. weight and width are not a problem. 3/8" is perfectly adequate so we used it in another bathroom. I guess this discussion is similar to the 2cm vs 3cm granite. 2cm works perfectly well. so does 3cm. If you like the heft, get the thicker material.

Total price over $7500, straight corner, door plus two shorter panels (door is on 5' side and attached to wall). Classic L-shaped installation. Invoice doesn't even specify door size, so I suspect it is standard 28", but I will ask. Hate quotes without decent breakdowns, so I'm unhappy already. I don't think DH is up for DIYing this. It's part of a whole house remodel and addition, so we're overwhelmed with projects and need to get this bath done. How much do clips cost? Also, we have hard water and calacatta tile in the shower, so both low iron and good coating are a must, even though I know they are adding some to the cost. Still, 1/2" Starphire for fish tanks sells for $15 a square!

Good for you, you did not accept that and they are getting redone. If done correctly...you should (or can) get away with NO vertical plastic stops. I try to avoid anything that collects gunk and requires maintenance. I measure and order all my doors and the gap should be 1/8"-1/4". Anything over 1/4" is too much for my satisfaction. 1/2" is totally pathetic. When this gap is done correctly, you will find you do not need a plastic stop to prevent water from leaking out. If you use a sweep on the bottom, that will keep the door in place where it needs to be because it puts some drag onto the threshold. Measuring takes time, a lot of time if done correctly.

Towel bar attached through glass = 1/2 inch. Be very diligent about proper structural framing on the walls on which the hinges attach, people tend to use any "bar / handle" (even on glass doors) as a grab bar.