Two very good coasters but an easy deccision in the end.
Wildfire is great, it's absurd that it even exists at all, almost has no right to be as good as it is. The view, the drop, the inversions, the relentless pace of the first 3/4s. But it does run out of steam a bt after the final inversion, i'm sure it'll be faster now than when I rode it nearly 3 years ago, but it still sort of feels a little like they had ran out of room with the ending.
Helix however is pretty much the pinacle of rollercoaster design and technology. Not in the sense that it's like, unarguably the best coaster ever and should be everyone's favourite or whatever, just that it feels like every coaster built previously was leading up to it, that they took everything that came before it and used all that knowledge to make a coaster as close to perfect as they could.