On the surface, both will come with a polished 4000 finish. Inside is where all the difference is.
Cyclone: 2.53 RG, .053 Diff (15 lbs)
Nail: 2.55 RG, .042 Diff (15 lbs)
The lower RG numbers mean that the Cyclone Torque Core used on the Cyclone should roll a little earlier than the Modified Doom core on the Nail. Also, the Nail has a much lower differential than the Cyclone. This means that the core strength on the Nail overall is weaker than the Cyclone.
To sum it up:
Cyclone: rolls earlier, higher flare potential = more overall hook
Nail: rolls later, lower flare potential = less overall hook
Both balls are good choices but I see far more Cyclones than I do with the Nail. Some in my league use the Cyclone and like the overall versatility with it. As in the case with Roto Grip and Storm, the Cyclone gives you a lot more ball than advertised in that price point.
