I've got an '05 Stumpy FSR 120. I've had the stock spring in the Manitou Black Super fork relpaced with the stiffer spring, to compensate for my heft (230#), but still the fork bobs while climbing, dives under heavy braking, and bottoms out HARD on drops as small as 18 inches.
Also I feel the fork has a tendency to pull to one side as it compresses - not a confidence builder.
Finally, I'm trying to deal with the annoyance of having the front wheel unweight while climbing over roots and rocks on loose surfaces. I've improved performance in this regard by winding down the travel (I open it back up for descending) flipping the stem over and moving the saddle forward, but it's still not optimal.
Any other suggestions for mods or a suitable replacement? I'd like to avoid buying a different fork, or paying for a new hub just so I can use a 20mm axle.