Hello,
Cool concept, JmOz. Magic: The Gathering players in your group will be calling them "Sliver Bracelets" ...
One question though - you say the bracelet will work for anyone who straps it on. If, say, Kinetik takes down one of your team members and puts on his bracelet to get the team powers, will the other team members become speedsters too, or will it only share their innate powers?
If the bracelet only works (for whatever special-effects reason) with the team's powers, I'd probably buy each character all the powers, with the bracelet-granted powers bought through a Universal OIF (and probably in a Multipower), with perhaps an additional Limitation for not working when the person who has that power innately is KO'd/not wearing the bracelet/out of range, and another Limitation, if (as Blue suggests) two people can't use the same power at the same time.
If the bracelet will copy powers from anyone who puts it on, I'd have to go with a VPP on Universal OIF, with Limited Class of Powers available (similar to Mimic Pools), Zero-Phase no-roll Pool shifting, and the other Limitations as above. It'd be pricey either way, but it does seem a pretty powerful ability.
Straight up naked Usable By Others doesn't seem to work for me; you'd need to give it Range, have line of sight, there are the issues of who's controlling the power and paying its END, and so forth.
The whole concept definitely sounds like something a properly evil GM could have good fun with, though.
Hope this helps!