The atom is very very reliable.. Honda Civic Type R engine.. And if you got some extra money to spend on it.. Get the big supercharger.. 300HP.. They say from a stand still you get to 100 in 2.9 sec and I think you do that in second gear no first.. If you also got more cash to spend on it get Magnisium wheels. Digital read out with all the gadget that comes with it.. Get big brakes and Brake adjester. The car is fantastic.. I usually see a radical at the track amazing machine no dought..
Good things about Radical:
Very fast track car and probebly faster than atom
looks like a racing car
Bad things:
1- Bike engine not very reliable and personaly I don't trust them enough.
2-Very low nose ( Great for track days but not for the road )
3-Looks more like a racing car than a weekend toy..
Conclusion:
If you want a track car only get a radical if you want to have fun on and off the track get an atom it is also trouble free and easy to maintain..