At least, I think this is respect to DFRPG. On the other hand, it could be a useful mechanism for use in a non-DFRPG game which was based on the DFRPG system. D&D Files RPG, anyone?
In that case I would have no problem with this. Heck, the whole D&D magic system is memorizing spells in advance, so this would be perfect for it.
For Dresden though, I don't think it fits.
I see it along the lines of an emergency set of batteries. If your flashlight runs low, you can switch batteries and keep going. But you can not put the extra set of batteries inside together with the original ones, you have to carry them separately (and might forget them in the car, for example).
Because there aren't any powers that can do what magic item rules can.
What exactly do you want to do?
Attack? Take breath weapon. Yes, it is not as powerful as an 8 shift enchanted items weapon, but that's ok.
Block? Take part of a toughness power. 1 point of refresh for each point of armor or 2 points of a block, or 2 exchanges extra duration. Has to be cast and the points can be applied as needed when casting.
Maneuver? Take half of a breath weapon for 1 refresh to only use the maneuver part.
That should cover anything you might want to do, and if not, there is probably a way to create a power for it. You could specialize channeling even more, to make a one-spell-wonder sort of power for 1 refresh, if nothing else fits.
The same guy that needs to spend 1 refresh to internalize that magic either drops his items from 14 to 10 or drops their power to 8and frequency to 4 from 9 and 5 respectively - which is a pretty hefty power decrease.
That is still extremely powerful (50 spells at a power of 9 without the risk of backlash or fallout!). You are getting a weaker form of modular abilities, because you can change your enchanted items around as you need them, without any fear of getting them taken away.
