Recently added a simple rail to the super-elliptical... I actually don’t necessarily feel the need for rails at all for a home game, as few players can zip cards around fast enough to send them off the table, and I’m as comfortable just leaning on the table top as a rail. But people seemed to want one, after one session of rail-less play. Upholstering the rail was a backbreaking task the first time around, and probably still would be the second time, though the learning curve is less steep.
Rather than built-in cupholders (which make seating locations less flexible), I’m using Brybelly slide unders. These have the advantage of allowing players to adjust their location, depending on which hand they prefer and where they are sitting, and they come in two sizes. The players not drinking anything don’t need one, so it makes forces clutter.
https://www.brybelly.com/products.php?categoryId=340&productId=347
I built the table foundation with just a single sheet of birch plywood, since part of the goal was to make this easier to move/set up/break down. But I felt once the legs were on that there was a little sag at the ends. So I rigged up a system where I used aluminum clamps to attach a piece of 1" steel piping down the center axis at each end. This provided a much stiffer surface without adding too much weight.
Other build note: Once the rail was on, I felt the table was too high with standard folding legs, so I chopped them down with a reciprocating saw about 1" and covered the rough ends with some rubber feet. Much more comfortable. I’m relatively tall, but some of my players are not, and there’s nothing worse than a too high table. (OK, there are some things worse...)
Overall, I am liking the playability compared to the huge, heavy racetrack table it has replaced. The table length is about 5" shorter, making dealing from the ends easier; the width is the same about 48", good for raking pots; and with the super-elliptical does seem to make a subtle but tangible difference in sight lines and reaching for cards/chips. Will post some pictures the next time I set it up.