There's a mix of abilities, from beginner to advanced. The important part is the ability to shuttle the boats for diwnwinds.
By the way, there are a couple clubs that have surfskis available to the members or their guests: BIAC in Redwood City (gobair.org) and BPRC in Berkeley (berkeleyrowingclub.org). I store my boat at the BIAC and paddle there regularly. Their club boats include Epic V5, V8, and V8 Pro. The Berkeley club has other options, but I'm not very familiar with them.