I like them, or at least they are growing on me. I like them for some applications, mostly for aesthetic flair or maybe on a defensive blade. I just purchased an Ultratech yesterday. I went with the tanto edge over the more drop point and double edge because I thought it looked "cooler" on an OTF knife. I bought the knife to mostly play with but also as a unique EDC at my office. I suppose the tanto might be a bit better at poking holes in an attacker, but I'm pretty sure I could ram a butter knife to the hilt if I needed to get someone off me. So to be honest with myself, I just like the way it looks.
I do have a "short" 12" blade Tanto made by Himalayan Imports. Incredibly light and ridiculously sharp. What it lacks in mass (compared to their other offerings) it makes up for in a very slicey belly and has more of an old school squared off and robust tanto tip that would jam through pretty much anything.