Whirlpool AFG5227 chest freezer

I hope you'll be able to help here. I bought the above freezer in 2001

and it broke down a few weeks ago. I'd bought a 10-year parts guarantee

when I bought the freezer, so called Whirlpool, and they sent an

engineer, the call out charge was A379.

He discovered that the compressor had broken, and said it would cost

approximately =A3200 to replace it, so he had to advise Whirlpool, who

would come back to me. Whirlpool sent a letter and said I could have a

new freezer if I sent a cheque for =A3140 (this offer was

non-negotiable and was valid until 20 June 08). I checked on the net

and found I could get the same freezer for =A3151, so emailed Whirlpool

and told them I could get it if I included the engineer's call out

charge, =A368 cheaper. They told me they'd used High street prices

(Argos sells them for =A3179) and it included installation and

collection of old freezer. I can put the plug in myself, and our

Municipality will collect the old freezer free of charge.

What should I do?

Looking forward to your comments, Elly