Try GTS
Hi there, I can recommend GTS at Bournemouth having just completed the CPL groundschool with them. The course material was pretty good, the support for distance learning excellent and the residential weeks prior to exams absolutely first class. The instructors are very experienced and well connected - e.g. ex RAF Navigators, consultants to the CAA, ex BA B747 Air Eng to teach AGK - and provide really excellent instruction. I cracked the whole course in 7 months while working full time, largely due to the excellent support the guys at GTS provided.
I am in your situation too, a PPL with 500 or so hours and now half way through the FI course.
Good luck!