Maybe it was me, but at moments it seemed like Cronenberg had borrowed the cinematic equipment and sets from one of those bad Skinamax films.
For example, when our lovely leading lady makes her way to talk to her editor and former boyfriend after seeing her stocking, a black stocking at that, teleported between one bee hive telephone booth to another bee hive telephone booth, the setting of his office looks completed handcrafted by the same folks who make classic episodes of Passion Cove and the like. (And yes, I know The Fly is earlier. But go back and watch the film. It seems that Cronenberg really has no interest in crafting a reality outside of the Brundle's laboratory. It is there that the film takes on a level of reality. Everything else rings of plasticity.
Of course, it is interesting that Cronenberg rarely ever shoots the film outside. We only get a few minor shots outside of Brundle's building and that is it.
What we also see here is some interesting acting by Jeff Goldblum who still seems to be channeling his character from The Big Chill. But, you do have to give Cronenberg credit. The last half hour of the film does well for horror, including fly vomit, falling skin, and melting flesh.
A look at the Cronenberg canon:
http://www.filmfreakcentral.net/notes/dcronenbergretrointerview.htm
