Hey Gou, I built one about 2½ years ago using modified IKCA plans and he's still going strong today, but I admit I don't even kick him full power. I also recently bought the IKCA ultraman on an ebay auction and have used other ultramen in the past. They are great and mount just fine (sorry rob) but you do have to mount them yourself and supply the base materila (plywood or other) so that could possibly suck. Can't beat the cost as far as dummies go, $200 delivered to you.
I also got a video from Kenpo Joe Rebelo and he did an interview with David German (TAI). Mr. German has a dummy called the kenpoman. with legs, a head and an arm that rotates 360 degrees. he did some really cool stuff on it, a great way to practice techniques, timing, checking, etc. There is also an ad for it in Blackbelt mag, but it is costly ($400+). He invited me to come down for a demo and a no-strings attached lesson, which I'll be doing in the near future, I'll be sure to pass on a review after I get my grubby hands on it.