I've been using a Spacemouse plus for a couple of years, now I couldn't work without one.
The other day I was at a clients reviewing a model on one of their PC's. Without the Spacemouse it was like having my left arm cut off! I had to ask one of the engineers there which icon was used for mating!
I would like to upgrade to the Space Pilot at some stage, having the LCD screen would be an advantage. That advantage would be significantly more when learning to use the Space pilot. I have memorised what all the mapped keys do in PARTS ASSEMBLIES and DRAWINGS, but it did take a while.
If I recall correctly my first week with the Spacemouse I thought it was a complete waste of money, it was so difficult to break the habits of clicking on icons, controlling the damn thing and using shortcut keys (I still tend to need quite a few shortcut keys).
Buy it, if you don't like it I'll buy it off you on Ebay --- at a discounted price of course.
Regards
John Layne