Hi there. Ive just gone through the powder coating phase with my Montesa. Ive had a few frames done in the past and I can safely say you get what you pay for. I used maldon shot blasting in essex on the montesa and they were amazing. I know you live in Glos but they do a postal service. The finish they achieve is incredible as they are automotive powder coaters and not industrial powder coaters who do a sideline in bike frames. I had the platinum finish which includes the blasting, rust reatment, priming, coating, and laquer finsih and it was about £160 including the swing arm. The finish is amazing as I am dead fussy. They even sent me colour swatches in the post so that I could be confident in the colour I wanted. The platinum finsish is gaurenteed for 15 years. I had a total of 16 parts coated and they never lost or damaged one. Give them a try.