What size table? its okay on 7 or 8 foot table. They play louder, you can hear the ball roll. There more prone to getting low centers. Another factor they don't settle into carpet as well.
A 3/4" slate is more designed to save manufacture cost, reduce weight, allow the use of cheaper materials to construct the frame of the table because of less weight to support. This slate thickness is scraping the bottom of the barrel when it comes to even being close to some kind of quality in a pool table