Since 3 weeks (use with 2 cameras), I have the Ex-Pro Battery next to the original Olympus and Voltway in use. Making a difference to original item, I could not notice until now. In Olympus Original Ladegrät the Ex-Pro will not load. The charger can charge the Voltway Ex-Pro with no problems. I can recommend the Ex-Pro with very good conscience as a cheap alternative to the original or as a replacement battery.
Greetings from Berlin
Franz Maier
Update 12/09/2013
Until now I have the battery in use daily. So far I could not find anything negative. He still works as good as my original Olympus battery. Currently I use the EX-Pro with the Olympus EM-1 in the battery grip.