I have 1/2" thick glass fixed side panels and 3/8" doors. I'd recommend 3/8" for the door. A 1/2" door will be really heavy.

I was stressing about the same choice for the french doors in our shower. In fact, I think I posted a question in this forum about it. Our vendor also recommended the 3/8 over the 1/2, saying 1/2 inch would be "overkill" and heavy on the hinges. We chose 3/8 and I'm glad we did--we saved money, and it feels nice and thick, not flimsy at all.

Same here. I was ready to consider 1/2 inch thick glass but the shower installer company wouldn't even consider it given our curbless design. 3/8 feels fine...not chintzy at all.

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.

Ours is 1/2", about 30" wide and supported off 2 hinges. IIRC, it weighs about 70lb. That really isn't that big of a load on each hinge. With the screws that came with it, they're only sunk into the studs about 1/2".

If you want it, go for it.

We used 3/8" starfire/starphire glass in our guest bathroom. It feels perfectly solid. We'd "upgraded" to the starfire glass, and for taller height glass, so didn't need or want to spend more $ for the thicker glass, too.

It is super helpful!