Off camera flash

I've been working with off camera flash for a little while now, first by use of a TTL cable and then with the aid of a Nikon SU-800 flash commander to give full TTL (through the lens) flash control - including the ability to run in high-speed sync up to my camera's max shutter speed of 1/8000th sec.

I've been pretty happy with how the SU-800 has performed and only recently started looking at ways to overcome it's main limitations; the need for line of sight operation and, being IR (infra red) in it's triggering, it not liking bright lighting conditions.

Now I know that PocketWizard are the most popular brand out there, and also pretty pricey, I decided (also my wallet helped the decision) to test the waters with something a little cheaper. I found a good price on a "1 light" set of Phottix Ares triggers and have to be honest that I have mixed feelings on the performance and reliability I encountered.

My initial testing revealed a fairly significant "failure rate" of approx 5% where I either had no flash triggering or what appeared to be a sync issue with a dark band over the image. This was using a Nikon D2x and a Nikon SB-900 at max sync speed of 1/250th sec. I even dropped the speed to 1/200th sec with no real difference in performance.

Is this kind of failure common to radio triggers or is something inherent to the Phottix - or to my aging Nikon D2x, or the SB-900?

I'm now contemplating my next move. Keep the Phottix triggers, and live with the photo failures; return it as faulty (will a replacement be any better); or save up and buy a set of PocketWizard triggers? Which, if all radio based triggers have a failure rate, will I be better off spending out for PocketWizard's?