In theory crinkle cut should be outstanding as they have greater surface area than straight cut and therefore offer the potential for greater crunch per inch, but they always seem to be undercooked.
For a similar reason, my nomination of worst fry style would be English chip shop style chips. They're generally fat and soggy with little or no exterior crunch, just flabby lumps of uninteresting starch that have to be drenched in salt and vinegar to be palatable. Wedges have a similar problem but are saved by the fact that they're usually coated with spices to provide a more interesting flavour profile.
