Another thought. Over the years I have used that extra circuit twice on the HMMH. In other words, do you really need it?
I use it all the time for the forklift, most recently when taking delivery of a new Ariens Pro 28" EFI/hydro snowblower and an 8' Fisher HD2 plow for my Dodge. Had to fetch them from down on the highway and bring 'em up my twisty steep side-sloping driveway. Needed to rotate the forks about 15* each way to keep the pallets level.
For the benefit of non-HMMH owners, the two levers for the front hydraulics are the same as the SEE, except for the red button. One lever raises/lowers the forklift, the other tilts --or-- press the red button and that lever rotates the load. Very ergonomic.
On the SEE, one lever raises/lowers the loader arms, the other lever tilts the bucket up and down. Another control would be needed to open/close a grapple -- the red button circuit on the HMMH. Taking the forklift off the HMMH and putting it on the SEE as-is, the forklift will go up/down and tilt, but not rotate, and of course there's no suspension lockout (although it can be retrofitted, but I think the struts are different).
So yes, I think I need it.
Same with the locking front suspension, come to think of it. An interesting novelty that I forgot all about.
Without locking out the front suspension, picking up a load on the HMMH forklift lowers the suspension before it lifts the load; opposite happens when unloading. Plus, the load bounces if you go over a bump (or hit the brakes). I personally hate all that, YMMV.
Placing logs on the firewood processor's feeder rack requires a bit of precision, so I don't want the suspension bouncing up and down while depositing the logs. So for my purposes, the lockout is more of an essential than a novelty, YMMV.