pretty much Peter.
They are used alot in power generation.
There are fuel control units in the aero versions which deal with changes in air density etc. Ground based ones its chuck the fuel in and away you go.
You can do some really nasty things to the ground ones over cooking them at 120-150% power output and they just eat it up if you can get enough air and fuel into them. You would never be able to do that to the air ones because instead of driving the fan they are driving a dyno, the fan would never manage to get the power into the air flow and they would over rev.
There is a rig in the north sea which has 5 of them onboard to provide power for pumping oil through the pipelines. If you were to get all 5 going at max chat it apprently could power most of the east coast of scotland.