I sell Xerox, Canon and Konica production equipment and have a ton of experience with Xerox. The clear is like a spot UV not not exactly, on the Versant it is okay but I by far like it more on the Iridesse as you can layer which really allows it to stand out. Others have mentioned but clear on the Versant will also come with Gold, Clear, White and Silver kit. This Kit will require you to swap all drums and toners including the housing, this change over is about 20 minutes so not something you want to do often. Also note that depending on your clients trying to match registration perfectly with clear is going to be tough when you are rerunning the same stock thats already printed from your CMYK pass. This is why the Iridesse also shines!
For the cost of the machine and kit its not a bad add on as it will set you apart from many other local printers but its important to fully understand it so you can market it correctly. I see Silver, White and Gold being larger sellers and clear being the "hey I can also do this". I cover MN, SD, ND, NE, IA and WI if you are in these areas and want to chat more I am happy to do so but I hope this information helps. Xerox does have a ROI calculator online for the specialty colors make sure you check it out!
Caleb
caleb.sundvall@loffler.com