I like glass. I had been using acrylic until @ejay-ibm suggested I give glass a go.
I haven’t actually got the reflective film on perfectly (yet, trying again tonight!) but so far glass seems like it is going to produce a nicer finish than acrylic.
Thin acrylic just won’t work. It’s too hard to get it perfectly flat so the reflection is distorted. Thick acrylic is better in that respect but it still scratches too easily. Glass is thinner than the thin acrylic. I think glass weighs about the same as the thin acrylic. Glass just seems better in every way except it will cut you.
Glass Pros:
nicer finish
thin
light weight
no warping
cheaper than acrylic
doesn’t scratch easily
Glass Cons:
it will cut you
Acrylic Pros:
it won’t cut you
Acrylic Cons:
warps easily (sometimes it’s already warped at the store)
scratches easily (sometimes it’s already scratched at the store)
more expensive
But this is all with me doing it myself. I wouldn’t be surprised if you found a very nice, big, professional-looking piece of acrylic with the film already on it somewhere. But based on my experience glass does come out nicer and lighter.