I got an assortment of LEDs from
www.rtbb.com.au to try out. I'm not a fan of the "change every lamp" idea, but they are excellent in certain feature areas. In AFM, the mode completed inserts are way too dark blue to let normal lamps light through well, and the LEDs work a treat. In Black Hole the lower playfield arrows have a similar problem, and LEDs did a great job there.
Unlike other suppliers locally, *every* LED I got from Greg worked, so not sure where he gets his stock but they seem good.