I'd like to give little more protection to the underside of our '09 Clubman S. The two options seem to be the Rennline aluminum skid plate, or the JCS GP2 plastic belly pan. The Rennline seems more robust and might provide more protection from rocks/ice/small furry creatures that get bounced off the bottom of the car during our upstate NY winters, but looks like more of a pain when carrying out maintenance. The GP2 seems nicely designed, but does it offer any protection, or is it mostly for aero?

 

The Rennline aluminum skid plate HERE is a great choice. I have an aluminum skid plate and it saved me so many times whereas my plastic one would have done absolutely nothing. The Rennline plate is aluminum and is most certainly more robust than a plastic belly pan. I'd recommend investing in one if you're looking for more protection.

 

Skid plates vs. Composite pan are very miss understood.
The fact is that anything major will push either one inward.

Aluminum will be better suited for ramp shape like debris interference. The downside is that it can bend and deform more easily, and possibly stay in bent shape that could more easily interfere with other parts of the car.

Fiber glass composite pan on the other hand may possibly crack if hitting a large and sharp object. But in most cases it will bounce right back and actually absorb stone chock a lot better than the aluminum which will transfer impact more directly.

Overall, in both cases they will be an equally good addition in protecting the engine from small to medium size impact, and will prevent unnecessary corrosion.

Personally I'll bet on the fiber glass composite pan any day. But they really are both good options.

 

I have the GP2 pan.

It is not plastic but as TG says some sort of composite material similar to fiberglass. It is very hardy. I had to cut a portion out since I have an automatic transmission. I do notice that the engine bay and mechanicals stay much cleaner with the belly pan installed.