+1 to the TK30 being (one of) the most under rated. I think part of it was to do with timing. The TK40 was released first, creating massive hype, shock, and awe. Then by the time they released the TK30, everyone had gotten used to the MC-E and it wasn't "revolutionary" enough to generate hype by that point.
Arguably, battery formats aside, the TK30 is the better light. Simpler interface (will always come on in the mode you left it, and easy to change back and forth), more compact/lighter, can be used in "short" or "long" configurations...
I bought my TK30 a while back, and was a bit disappointed there wasn't more info about it on CPF. I still prefer it over Fenix's current offerings, because I dislike the "two-button" design philosophy that Fenix is using for everything now. So for now I'm sticking to my TK30 and skipping the latest and greatest TK35, 41, etc etc even though they may be a bit brighter... but really, once you've hit 500+, are you really gonna need the extra two hundred lumens from the XM-L?? Probably not; it'll be brighter, but probably won't make any difference in real world usability/performance.