The design matters a lot: it needs to be critically damped, or nearly so, such that the scanner responds to a roll quickly without swinging wildly. If you do go this way, get recommendations about the specific product.
I had a manually controlled tilt fabricated on my stern radar post. On the one hand it is clear that the radar performs a bit better when it is level rather than shooting half the signal up in the air and half down into the water
. OTOH modern radars do a great job of compensating for the different levels of return. After a while the performance improvement wasn't enough to motivate me to climb back and adjust the tilt, so it isn't that big a deal in my book. YMMV
Probably the biggest problem with gimballing is what it does to the cable. The old analog scanners had 15-20 small wires in the cable, which of course started to break after continually flexing at the gimbal. The newer digital scanners often only have a heavy duplex power cable attached to an ethernet or USB data cable. This should be more robust, but still the data cable contains small wires. At least it would be a lot easier to repair in the field.