I got a Madrat And I am in a position now to upgrade to brushless.
If you plan to race at your club I have been advised to go for a sensored set up.
Have you looked at this?.. I reckon its pretty dam good value for money.
http://cgi.ebay.co.uk/INIX-Racing-60...item2eb2fd5df0
Its sensored so no coggong issues.
Theres a 10.5t and 5.5t option as well but ireckon 8.5t would be fast enough for me anyway.