The benefit of polyurethane is it's a stiffer material so less movement is allowed, but they do wear out fast (IMO they have less than half the life of rubber). Some of my suspension rubbers were new 3 or 4 years ago and now their showing signs of wearing out and I'm a bit annoyed they only lasted that long

If you want to fit new bushes every year or two than go for it but I want no hassle motoring.
They can go brittle so they break and crumble away once they start to deteriorate, so if you don't check them you could end up with no bush at all. They can also go slimy and deform a bit.
I wouldn't use them on a road car unless your going to give it a full check over every month and be prepared to put new ones in whenever they start to show signs of wear. With rubber you can run them a bit longer after they start to deteriorate simply because they don't deteriorate as fast.
Also with engine stabilizers I reckon use the rubber ones because they are softer so they absorb some of the hash movements of the engine.