There is a thread on here that touched on this a little while ago.
The conditions aren't easy to get removed and if you have to get a mortgage you will find that a lot of lenders won't touch a property with an Agricultural Tie.
Also please be sure that you comply with all the conditions in the tie. I know of someone who bought a house with a tie, they didn't have to get a mortgage, but the people who enforce these things are now making them put it back on the market.
Crikey I sound like a real negative Nelly!!!! Just be careful. You don't want to end up with a property that you then find difficult to sell when you want to.