The J&S is a nice unit, i had one but I now use a Pitbull because of the "table" that allows the bike to be rotated while lifted. This makes it better for me, I can sit on a creeper stool and spin the bike as I clean/detail. The J&S is just as good of a lift (no better IMHO) but does not offer the roller bearing supported table.
I have noticed several lately on Craigs list here local, might check that. Back to your original thread topic, I know of none with 4 pivot wheels but they have the pivot wheels at Home Depot, Harbor Freight etc if you really want them.
That being said, I have not seen the Pitbull guys at Daytona for awhile, R they still in business?