I just had a look on the medusa site, they have data loggers now! And one you can fit to the car while it's running called an 'Oracle'. If I raced I would defeinitely get one. Hobby Wing and Medusa has got to be a good match
Having said that I haven't tried the combo.... yet! But the medusa was silky smooth on the mmm v3.......the motor still works!
I've heard the HW can take a beating but I'll soon find out as I've got one but haven't run it yet.