yeah, the center of the vinyl is wasted for the benefit of a seamless rail, but I think its worth it for the cleaner look.
While many use billiard cloth, it is pretty expensive. I used velveteen. The cards slide really well on it and it appears to be holding up well. After several hours of play it is not balling up or anything like that.
I basically bought everything at Joann's. Being a preferred customer (I know, pretty sad) I had a bunch of 50% off coupons for the vinyl, velveteen and foam. There are also some online distributors that sell some good table construction supplies.
I used one inch high density foam in the rail. Rather than waste the center, I stacked a second layer on top of the first, which is why my rail looks like its on steroids. But it is very comfortable.
Below the velveteen playing surface is headliner foam. This makes it really easy to pickup your cards, or just peak at the corners without lifting them from the table.
I could go on for awhile about construction, so if anyone is curious or wants more details, let me know.