If you have little or no tractor experience go for hydro as you don't need to UNLEARN gear reflexes.
If like me you have 35 years gear reflexes, then stick with gears as many years wears a very deep groove. I tried hydro, but on my hills for me it is a bad idea. I know another farmer who loves his hydro, HOWEVER he made a strong point that learning hydro reflexes after 20 years of gears wasn't easy.
DK35vince has best summed things up.
If like me you have 35 years gear reflexes, then stick with gears as many years wears a very deep groove. I tried hydro, but on my hills for me it is a bad idea. I know another farmer who loves his hydro, HOWEVER he made a strong point that learning hydro reflexes after 20 years of gears wasn't easy.
DK35vince has best summed things up.