Welcome to the forum! Well to answer your brake question, it depends on differnt things. Most people use a magura hs33 rim brake becuase of their good bite and hold and a wide selction of brake pads But people use Cable discs such as Avid BB7s or hydrolic discs Hope Mono Trials. Poeple have they own personal prefernces on what to use i would go with a magura becasue they are easy to set up and if looked after last for ages. With the Dob frame, they are very very weak so expect to find some crack a few months down the line, id take a look on www.tartybikes.co.uk and have a look at the new Zoo! frames. And never buy from TrialsUK!!!