I have the EX150Mkii and it's a great set of lights - power output is really consistent (to within 0.1 stop), and build quality etc is also really pretty good - I was spoiled by free access to a fully Elinchrom / Manfrotto stocked studio (my last job was for a national newspaper
), and I've been really impressed with the performance of this kit. The only thing I miss is having a boom arm and a decent sized softbox, but given the 2 light kit is less than a 580EXII, I can't complain!