Sorry if I point this oil cooler thing up again, but I read on a post that the problem with an oil cooler is that they use external lines and the cooler itself is subject to punctures & damage by branches. If you get a hole in the oil lines or the cooler, that could ruin a day's ride.
Also the oil cooler's main purpose isn't to keep the engine cooler. It's main purpose is to keep the oil from getting too hot and breaking down it's viscocity.
Unless you're hauling heavy loads or plowing, I would save that $100 for something more useful.
This has some sense, the best thing to keep an engine cooler is adding a fan just like my 700 had. Do they sell fan kits for 350's ?