I started a similar thread to this a while back also and I got some different responses so I was unsure whether it would be worth it or not.
Anyways I found a good deal on a new one so I figured I would give it a try.
I had been running a stock cdi previously and then added the MSD by itself without adding any other mods at the same time to see how much of a difference there was(there was already a bpipe, head, and prop on the ski).
This is what I noticed about the MSD Enhancer:
1. The ski started much easier(not that it was hard to start before, but with the MSD enhancer it started much quicker)
2. The throttle was much crisper and had absolutely no lag(I especially noticed this when reving the ski out of the water)
3. The ski sounded different
4. I noticed a slight gain on the bottom, but it really didn't make the ski pull any harder. Once again the throttle response just improved a lot on the very bottom, but once you were past the initial throttle hit you couldn't tell the difference until the pump unhooked or you were in the chop.
5. I definitely noticed a difference when running wide open or messing around in choppy stuff due to not having a rev limiter anymore. I didn't realize how much I was actually on the rev limiter with my stock cdi(modifying the stock cdi will produce the same result though).
Ultimately I am very pleased with the enhancer. I feel the $190 I spent was worth it and really allowed me to get the most out of my ski being that I already had a bpipe, head, and prop.
I would recommend it, but just don't expect a knock your socks off difference like you would with Total Loss. You will notice a difference and improvement, but you have to decide for yourself if that slight improvement is worth $200-250.:biggthumpup: