I finally played with a Ninja in Ikari. The FO Combi Rifle. I've got to say I really liked him. Just the reliability of being able to be in the mid-field and no chance to be hurt if i don't reveal him is really nice. I took the FO Combi because I was playing Frontline and wanted to put him in suppression on the last turn. Which worked well. I had him in good cover in suppression and anyone trying to dig him out were going to be anywhere from -9 to -12 or more to do it. And good luck using a CC guy to do it. Someone I'm going to be using more often. Side note: I'm using the Nomad Specter from Icesstorm as my Ninja. I've cut off the knife and put an old Yu Jing sword on his back. Going to be painting him up pretty soon.
Ninjas with combis are really nice. YJ and JSA players tend to fall back on the KHD guy for cost effectiveness, but not being able to go into nasty suppressive fire or really kill things at range at all is a major downside.
That's where you realize that Military Orders have the infiltrating TOFOOS with BS 12 for a mere 27 points, as compared to 29 points cheapest specialist ninja, and suddenly understand that somehow knights come with AVA: Total for one of the best specialists in the whole game...
I really love the Ninja FO or AHD, for the same reasons. The utility of a midfield TO Combi rifle is just fantastic. The KHD is obviously the cheapest specialist choice, but the lack of utility drives me nuts most games I use them. It definitely helps that Ikari has so many inexpensive options that you can splurge a little on a ninja.