Andy
I see you intend to go the ATPLs later on.
A couple of tips:- Get a Class One medical from Gatwick BEFORE you start your flying training.
The Thom books go beyond the PPL level and though not enough for the ATPLs they are very good reference put across in a clear method.
Though the Transair PPL package sounds okay, for an ATPL you are going to require a CRP5 (or equivalent) navigation computer, I believe the package offers the CRP1 - try talking to them nicely.