I talked to a bunch of the Witch's Rock campers last March when they stopped in Guiones, and they didn't have any complaints. Of course, if you fly TACA, I think they have pretty reasonable board fees.
I've stayed there twice and have always brought my own boards. Yes, they have boards but for the most part they are NSP's and mostly all long boards. They did have a couple of short boards, most were not of the highest performance and they are usually grabbed up by other guests and not available. If you are anything other than a beginner, I would recommend bringing your own.
My experience was like "CharileInOC" until I went back in Jan of this year. I was super happy to learn they have a full quiver of new boards beyond those NSPs. If you are a typical shortboarder, bring your "go to" shortboard. Witch's has a full range of fish, funboards, & longboards. All new and shaped by a SD shaper whos name escaspes me. The camp has a repair shop on-site now as well as a surf shop. They take very good care of the boards. As long as your are signed up for "tours" and not lessons; you should have full access to the new boards. They let me just use the same board all week once. A new 6,4 Rocket-fish, quad....really fun. I know some of the boards are posted on-line somewhere. I just went on a trip to Southern CR & Panama with Joe from WRSC; we surfed his boards and they we in great shape and super fun.