It may increase shutter-lag a little, but I expect the metering is quick compared to the mechanical stop-down, and obviously you won't know the shutter speed before hand. But for those more point-and-shoot moments, or for handing to other people (as previously mentioned), it would be fine. When in 'M', the green button can still work as now, so you'd lose nothing.
Love, Light and Peace, - Peter Loveday Director of Development, eyeon Software
