The Premier 3000 are the best clippers you can get and they're great value, they were recommended by Beaconhorse who also has them.
They are heavy duty clippers for the price of medium duty ones, they take Lister blades and they're just great. Quiet, lightweight but powerful. I clipped my very very hairy Welsh the other day with no problems-
Oh and the company i got them from, Farmcare UK are fantastic too, i ordered them on a Friday at 4pm they arrived the next day, Saturday at 9am!!!
BTW i swapped the blades for Lister Fine blades for an extra £7.
FArmcare are brilliant. I love my Heiniger Progress clippers, very light, easy to use, and very quiet, and heiniger have always been very highly recommended to me.