I've been trying to make friends with my wireless PTTL flash system (K10D, 360 flash, Metz 58 flash). I really wanted this to work, but I've discovered a few things:
Line of sight really means line of sight #1. The Metz flash has it's IR sensor on the left hand side of the body, which means if you hand hold it to the left (so you can hold the camera in your right) the flash won't see the control flash. I spent a great deal of time with that one until I figured out holding the flash upside down in my left hand gave me back IR line of sight. Pain.
Line of sight really means line of sight #2. Neither the Pentax or the Metz shot reliably tucked behind a tall indoor plant. I used the built in flash as the control flash, so maybe a using a bigger flash as the master would help get the control flash through the plant leaves. Unreliable performance.
I also might have had problems with nearby reflective objects... had a devil of a time getting a proper exposure with wireless PTTL using an umbrella reflector. Everything was badly underexposed. Still scratching my head over that one, not sure what was up.... one answer is the reflective umbrella was somehow confusing the control communication between master and slave.
In all these instances, I bailed out, used my Cactus V2s and used the histogram to tune in my exposures. Failure rate on the V2s at this point is about 1 DNF (did not fire) to 12 good ones.
So far, the hassle factor for wireless PTTL is quite high for me.
So I'd say ... unless you've got to have 100% reliability on your wireless setup, go for the Cactus V2s, maybe try running the flashheads on auto setting. It's maybe 50 bucks investment, and if it doesn't work for you, you can easily move the triggers in the forum marketplace.
good luck,
germar