Using one of these, bolted to a wooden chair (a homebuilt one).
The thing is connected to the bass output of a 5.1 speaker set, via a dedicated 100W amplifier ... works fine.
Feels good, adds something to the immersion. (Won't work for sure when I am using headphones for main sound, for sure...)
It rumbles on the low game sounds, so yes, on the guns, on the engines ... on big explosions...
(Sorry for the big image, couldn't find any smaller one... the real thing is about 14cm across...)
The only issues I've had was in the overheat department, if used too long, too loud, some woodburn can be smelt, and basically, a heated seat... next, the thing itself burnt out... no flames, just technically I mean.
(I have one spare left, for sure!)