Agree with everything Zig said.
Keep your shutter speeds up. I try to not let them drop much below 1/800 or 1/1000 second when I am using the EC20.
I'm also considering buying the 50mm f2 macro, mainly to use with my E-PL1 in manual focus mode. If I do, I will also be carrying the EC20 to convert that lens into a 100mm f4 macro. No doubt, it will find it's way onto my E30 as well.