The Speed Passion combos are great. The Reventon S And R speedos are of great quality, and are apparently the same under the the casing as the more expensive LRP Spin Super and Spin Pro. You can go for the 10.5t Speed Passion Motor, the 13.5t, 17.5t or even the 21.5t. Plus, they are only £65 from ModelSport.
Link to the 10.5t-
http://www.modelsport.co.uk/speed-pa...roducts/379166