I know this thread is getting old and you probably got all your testers, but even so, I would like to propose myself for beta testing the GH-505 if there is still some more places.
I bought the GH-625M in june last year. After two months, the battery would not charge anymore. I felt it was because I forgot it on charge before going to work. When I came back, I heard a shrill caming out of the watch. I was a bit perplex about what to think of the quality of the watch (no charge protector???).
Jesse in GlobalsatUSA offered me a pretty good customer support. After receving a new watch, automn and winter arrived in Montreal, Canada. I gave the watch a try and start to practice my marathon training in the cold seasons. I know it was not a long winter but I was really surprise to see that the watch did pass the cold test and from that time I fall back in love with it. I must admit that it did froze one time (all functions was unaccessible), but I can't tell if it was because the memory was full or because the weather was cold. Anyway, I did reset the watch and after that, when it was cold and windy (about -20 celcius), I placed the watch under my sleeve and I always been able to track my workout. Nice, what a good surprise!
As for the GH-505, I think it will get the two biggest improvment I was looking for: the submersibilty and the interval training. I wrote a few times to the tech support about setting up the intervall training to the GH-625M. They told me that they weren't able because the processor was already loaded. Interval training is the technic I use to improve my average speed. Saving every time I stop running when doing stop and go is not really effective. So, like abdominizer and others, I will really enjoy and test this feature hard.
As for the submersibilty, it will it will allow me to try what I wanted to do since some time already: the half ironman and maybe the ironman as well. I just moved near a water canal where there is a large swimming pool and a long cycle track. I feel like to try this adventure. Even if running remains my main discipline. I just have to wait for the pool to heat up with the coming days...
Good luck to all and I can't wait to see the improvements that you guys will bring us ;-)
Mac os X user with parallel desktop used only to run SportRack and S-Sport Training Gym.
And excuse my english by the way (I am a french Canadian)