I live in/am buying a place that used the forms to lay a path, back in late 90's.
Take the time to do the ground prep: leveling, compacting, etc. Can't tell you how many times I've tripped over loose 'tiles' on the downhill side. Watch the rise/run: pretty sure mine is too steep by a couple feet, thus contributing to sloughed off outer 'tiles'. :whoops:
And don't use the pebblity post-setting stuff, unless you have tuff feet. Those pebbles hurt, and aren't much fun to shovel snow off of either!
That said, I've not chucked the form, intend to use it once I get past the 'terraforming' part of home-ownership in the mountains.