I have one on mine, it works well, I removed the temp control for turning on the fan and have it hooked up to the brake light, if the brake is on, it's on, certainly don't need it on if I'm moving. My oil temps were running really high (280+) before installation (no factory cooler), they stay around 220-230 now in 90-100* days. Installation was easy, I will say get the stop for the filter adapter though, mine spun the first time I tried changing the oil, ended up making one myself. They have good service also, I had an oil leak about 6 months after installing it, the elbow connector at the cooler had the threads shredded when "they" installed it, another was sent and to me in a couple days, no charge (as it should be), they sent a whole new unit minus the filter adapter. The cover for it is kinda cheesey, if my bike wasn't black I'd probably have it painted.....
That said, not sure I'd remove an existing cooler to put this on. The factory cooler is plenty and there are fan kits available for it if you feel the need to blow some air across it when stopped.