D300what are you getting as your next body?
The remaining specks need to be washed off with solvent, I clean the sensor every other week with my Giotto rocket.Didn't come with the little wipes? Thanks to the coral dust, I have to clean mine usually about once a week
The 5D won't take Canon's 10-22mm lens. You'd be looking at the 16-35mm f/2.8 L II for an ultra-wide to fit the 5D.invest in some equipment aka the 5d 85mm prime a 70-300 IS and a super wide like a 10-20mm ish lens.