This is a showcase title, featuring two half-length stories each issue, with issues produced bi-monthly. Both stories are by unrecognized new talent writers and artists, and the quality varies accordingly. The stories are not particularly tied into the mainstream continuity, so if your budget is restricted and you are looking to collect only a couple of Spidey titles, this is one you can probably drop without too much impact. Still, it's a good collection, with a few gems here and there.
The first version of this title Spider-Man Unlimited was originally developed as a place to put longer Spidey stories, and ran for 22 issues in the '90s before being canceled.
It was later resurrected Spider-Man Unlimited (Vol. 2) in 1999 as a sort of twisted Spider-Man: The Animated Series/Fox TV spin-off that lasted only five issues before also being canceled.