I've started doing some night photography of friends who spin fire. I'd like to pick up an entry-level flash and a cactus system to get some off-camera lighting. However, I want to set the flash to 2nd Curtain Sync. I was looking at the Sunpak PZ42X for $150. However, their website says that it won't sync with the 2nd curtain on Canon cameras. I have a 50D. Is there a workaround? Can someone suggest a better flash in the $150 price range?