Some of your first-studied subjects are the hardest regardless of what they are. This is because you have to develop your brain into study-mode. I sweated over Ops and Instruments because of this, but looking back I reckon I would get better marks now.
I would say Air Law without the Question Bank would be nigh-on impossible. Jolly decent that the questions are therefore in the public domain
Met is one subject where you have to be able to recreate the picture in order to visualise then answer the question. Using Bristol's Question Bank will soon have you spotting commonly-asked subject areas. Crack these and you should get a pass.
Gen Nav is very mathsy. You need a good teacher also to show you the different chart projections, go through convergency and crack stereographs. After that the other elements are relatively easier. Work at it and the penny will eventually drop.
Perf/PoF are also concept based and it is one of those subjects where the UK exam setters seem to be, comparitively-speaking, actively introducing new questions. Two tough little nuts to crack.
Having said that Mass and Balance only has a few concepts to grasp and is nto that hard to pick up. However the total makrs on the paper donlt add up to much so you have a slim amount of questions to get wrong. On this account, I guess you could say M&B is a tough one. My lowest score so far (83%).
Flight Planning? Some M&B fuel/loading guff, PET/PSR formulae and chart techniquefrom Gen Nav, thereof you have most of the answers in the Jeppy manual
