This is the same answer I gave on a baler thread.
If you are looking at used ones to buy, unless you can buy for scrap price gehl anything isn't worth it IMO. Gehl has been out of the ag business for many years now and parts are very hard to come by with some things. A farmer I am friends with had to junk his 3-4 year old forage chopper due to he could not get the parts he needed when it broke. I know others with disk mowers and can not get parts either, their machines are a little older. I believe it was 2006 when they stopped all Ag products to focus on construction only.
I would look to see what you can get for parts. Much of what Gehl made for ag you can not get parts.