Depends. Does it really have any game effect, for example, can the character make it a fancy dress when needing to get into the swanky party, then tough street clothes afterword when walking the back alleys, then (etc.).
If so, I'd slap Variable Special Effects at the +1/4 level.
Or, as mentioned earlier, Instant Transform (FREd, p.152)
If not, it's SFX, no points necessary.