I have an 8H. I found that with material above about 5" I have to back the feed speed down to minimum to keep the
chipper from dragging the rpms down. That's with 32 pto HP. Yours has a little less. It's the same with all of the tree species I chip- madrone, bay, tan oak, doug fir.
The 8H's feed control is pretty much either full speed or very slow. It's because they used a 16 gpm flow valve on a 3 gpm system. I replaced it with a 5 gpm valve and that lets me use intermediate speeds. According to
Woodmaxx the MX series does not have this problem.
On the 8H the bed knife is way down in the chute. I'm 6', thin and limber, and I can just barely get in there to replace the bed knife. Most people are going to have to take the chute off, and it's heavy.
The 8H's hydraulic tank's cap/vent is on the back left corner of the tank. My land is steep. If I park the tractor so the vent/cap is on the low side, it can start dribbling oil once it warms up. The MX being hydrostatic probably would not do that.
Other than those fairly mild issues the 8H has been reliable and works well.