Acrylic over glass overflows is quite common actually. Although usually for glass overflows, instead of teeth, you usually see black eggcrate. This might be slightly advantageous because eggcrate is easily replaced whereas a broken overflow tooth might not be as easily redone.
My 280g was built by Bow Valley, although it was 3 years ago. I'm aware of their reputation but they were fine for me and based on my experience alone I'd have no reason not to go back and have another built. That said, I know the tanks that Albert & Dennis build are fine too.
Just be firm with what you want when you speak to a builder ... it helps to have drawings. I found there were a couple of things I wasn't that firm on and I got talked out of doing (for the sake of a lower cost) but in the end I kind of wish I had insisted on - the problem was I didn't really know what I want so I kind of let the builder steer me on a couple issues. Looking back, now that I have the tank in the spot I want it there are things I wish I had done differently (eg. overflow in particular). Oh well, it is what it is, I'll live with it since the alternative is .. well .. not practical. So my best advice is plan this as detailed as you can, do some drawings and say "This is what I want. Make it so!"
PS. Welcome to Canreef!