[mcain]

You''ll get 12 opinions from every 10 people you talk to about this topic. When we bought this boat (43'' cruising sailboat), it had main furling and I really didn''t want it. I figured the complexity and chance for failure was not worth it. After almost 5 years with it, I love it. Often we unfurl the main on short trips where we would not have bothered otherwise. Like everything else, don''t stress it beyond design parameters and you are OK. Be very careful about using them as a reefing system--when partially furled under heavy air, there is a lot of stress on them.
Our system sits in an extrusion bolted to the back of the mast and is by Forespar. Not quite an "in-mast" system, since it was added later. Loose footed, no battens, hollow roach. For racing, I might object to the loss of sail area without battens. For cruising, the sail sets very well and I am very happy with the set.
In short, good experience for me and I would have it again.