If I were getting tints done again I would go to Pentagon.
Without a shadow of a doubt these guys are superb and are undoubtedly the best in UK at what they do. They are potentially going to charge more than many people out there, but I think you'll struggle to find anyone better.
Besides, if you're spending upwards of £30k on a car, a couple of hundred pounds difference for something so quality-sensitive is a small price to pay.
http://www.pentagonglasstech.com/index.php
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Gone but not forgotten:
325i M Sport (E92), Black Sapphire, Coral Red Dakota, 19" 225's, Seat Heating, 6FL and de-badge
Replaced by 6.2 litres of AMG powered C class.