The title is a bit misleading. Proton is not the 2nd best selling brand in UK.
The Dealer Attitude Survey, undertaken by the National Franchised Dealers Association placed Proton 2nd after Lexus on the helpfulness of parts staff and 2nd best (alongside Toyota) in terms of technical support hotline.
Proton dealers were clearly very happy with the company and it reveals a synergy between the manufacturer and the dealers.
Links:
1. Car Pages
2. The Star report