Horizon is at Elmsett, don't worry about it being inside the Wattisham MATZ. I've been in and out of there for years and I've never had a problem.
Bill Stitt is the CFI and they have a C150 aerobat Texas Taildragger. Not a bad machine, as it has had very little use compared to the average school machine. You can do an Aero's course as well!
The Wx at Clacton can be interesting, especially with the runway being orientated N/S. Talk to Mark at CLN, he'll sort you out.