What kind of opponents are you looking for? I am not familiar with Hot Fuzz, so I am lost there...
Hasslefree usually does seem smaller than the majority of other figures, but that is because Kev tends to sculpt his figures to a more realistic proportion than other companies. However, when you take into account that people are all different sizes, they work just fine together. I have a mix of figures I used for a Superhero RPG campaign that were a mix of Hasslefree, Heroclix, Superfigs, Reaper, and Foundry, as well as the occasional Games Workshop, and they mixed well enough. Of course, I am not as furious of a scale monkey as some.