Sample pallet exempt from duty & vat?

[Del Piero 10]

I'm looking at bringing in a sample pallet for products from the UK worth £5000. I've been told samples are exempt from duty + vat but if it's over a certain value it's the usual duty + vat charges.

Usually I prefer local distributors for vat, supporting local companies & for local after sales support. The product I want to bring in is unique & no other manufacturer comes close.