Dave,

I have a bit of experience with this. On my MC28SP, I had Race-Tech (in the colonies) rebuild and install a gold valve kit in my stock shock. If I had access to high pressure Nitrogen, I think I could've done it myself after the experience of rebuilding many front forks. Shock was fantastic! Much better than stock. But, I kept dragging hard parts (pipes and rear-sets) since I couldn't raise the rear end.

Next I bought a used but recently rebuilt Fox shock designed for CBR600 F2/F3. I modified it to fit the MC28 chassis. If you have access to a bench grinder and drill press, you could do it yourself. I think I was running it with about 15mm extra on the ride height which also allowed me to raise the front end a touch. The bike turns in much better and it's really nimble but I might have to give the rebuilt Showa unit the nod regarding feedback. But, there's no massive noticeable difference between them.

If you fight in the welterweight/middleweight division, say less than 160lbs (how many stone???!!!) or this is a street based bike, I'd say go with a revalve and rebuild. If you can't pass up a chip shop to save your life or this is a race bike, chase down a F2/F3 aftermarket unit that is ride height adjustable.

Scott