Neil,
No, I don't think I have, but only because I haven't yet got a result with LM that I consider cleaning. Having talked to lots of people I think the guy's in the box seat here are the one's that offer the whole range of cleaning systems and not just one. I have always believed that as a professional carpet cleaner you should have the means to clean any carpet regardless of age, colour, soil conditions, or location and the only way of doing that is by having all of the cleaning systems available to you - but that's just me and many, especially those down the LM and VLM only routes will disagree, some quite vehemently, but if it comes to the point of becoming hatred to a fellow CC'er, then you can count me out.
Simon