Have been with Flying Time for a small amount of my hours building, CPL and have almost completed the IR.
Hard to compare to other schools as I haven't been to any others for commercial training but my experience has been very positive overall.
Generally a very well maintained modern fleet with good availability.
Excellent standard and range of instructors from young to old with a wide variety of backgrounds.
Ops staff are a good bunch who will do their best to help you out as long as you play straight with them.
All courses are pay as you fly with a very minimal deposit up front, (the figure £350 rings a bell, certainly the right ball park but it may not be the exact figure).
Shoreham seems to be a good place to fly from. NBD/DME and RNav approaches at the field with a decent selection of ILSs near enough.
The sim is a nice FNPT2 with exactly the same fit as the DA42s you fly for real.
I cannot comment on the ATPL ground school as I did mine at Bristol other than to say the guys who I talk to on the course seem to be happy and getting good results.
The only other thing I would say is that they don't strike me as the kind of school to hold your hand and wipe your a** if you know what I mean. They are a professional training establishment who expect you to act like a professional, turn up on time, be prepared for your flight, go away and research things and find information out for yourself. I relish that way of learning and don't want to be spoon fed everything but is you want all the answers given to you on a plate this may not be the place for you!
If you want any more info feel free to PM me and we can chat!