It is the same rack and I'm guessing different people sell it or perhaps put their name on it. The one from REI had a sticker fro rackbiz.com
REI says it is about 45lbs. I'm gonna guess all the swing away styles are heavy given the weight the arm has to hold if bikes are loaded. Softride was the only tilt style rack that I can across that would fold down with bikes on it. Having tested it with two bikes, it would be very hard with a tandem and/or 3-4 bikes to lift it back up.
The softride didn't sway but I didn't drive with it either. I believe they will all have some bounce to them on the highway and I've found that I also have to tie down the wheels and the bikes to each other and then to the rack with bungee cord to minimize any movement.
Good luck.