My experience at Kamakura's Teppan lounge was luke warm and it was kind of an awkward experience. Sure, watching the chef (with mad knife skills) flip an egg with two knives and not drop it - is pretty impressive... but as far as eating a hot meal... it is practically impossible.
You have to wait for the veggies to be cooked for how many ever people are at your table & then the meat is served up last. Now you're looking at luke warm veggies with semi-warm meat. It just takes too dang long to get the entire meal on your plate.
As for table conversation, last time I was there -- we were placed next to people who had one too many drinks, who were super excited about the war in Iraq and were definitely racist as hell. Wow, get way to start & end a meal. I really considered buying a drink just to throw it at them.
Either way, the food is eh for 20+ dollars. For a one time experience, I say it's worth it. But I am not all that into sitting next to strangers especially when their racist remarks make me gag.