Mirror Master Vs Spider-man

No prep.
No BFR.
Midtown Manhattan.

No prep I don't know..his effectiveness without prep seems to be vary. Though with prep MM would stomp.

Without it I don't know, Spidey should be quick enough to shoot webbing in the guys face before he can do much of anything.

In a comic with PIS, Spiderman would beat him like he beats many of the characters that he has no business beating (for example; The Spot, Sandman on a beach). In a forum match, I don't see how Spiderman wins this.

^^^Really? That one sided against the wall crawler? wow!

In a featureless environment m, Mirror M has no way of winning this.

He just doesn't have the tools to defeat certain opponents. It's not a slight against Spiderman or anything, which is why teams like the JL and Avengers exist. To take on threats that no single hero can and all that.