I've got one.
When its on the boat it's up in the tower.
Rubber Matt under it.
30 amp cord down to the boats shore power plug.
I mainly use it if staying out over night tuna fishing.
It runs 7-9 hrs on a gallon of gas but the accessory gas cap to an auxillery fuel tank is $ well spent.
Nothing worse that having to refill in the middle of the night with the boat rocking & rolling.
Just to make it quieter. Never been close to one...
Nothing special for a rubber mat.
Basically I use one so the Generator doesn't slide around.
A little more vibration dampening is a benefit also, although these Honda's don't vibrate much at all.
A 2kw unit is putting out a little over 18 amps at full load. A 3kw a little over 27 amps. You need to check the current draw on the unit and the pump. Start up current could be a problem if your at or even close to the maximum current.