They've held their value well, hundreds (possibly thousands worldwide) preserved and a handful still in commercial use in the UK. Marshalls advised against using power start cartridges except when there was real need- first start of the day in cold weather, as a lot of soot and strain on things was involved. It's easy enough to start them on the handle, heave ho and get all those cwts spinning...
I've done a fair bit of cultivating with a friend's machine, but as you say it's winching and recovering, or driving a threshing drum/sawbench where they really shine.