Good for a few strikes, at best. It also wasn't true invisibility, iirc, but more of a predator-like stealth mode. Once MNer has a bead on him, that advantage is over.
I don't know, once upon a time Venom was basically a slightly stronger, much more durable Spidey, but lately haven't symbiotes become Lovecraftian horrors that could bite Luke Cages head off?
I haven't really kept up with Spidey lately, but that's how I remember them during the Dark Avengers/Siege period...