Hi Kuma. The blue one is a G-100-2BVMUR. The watch to blame for my starting down the slippery slope of G Shock collecting! I just googled the GW3500B and it is quite similar, though mines alot cheaper. Is it the black and yellow you have? If so very nice!
I love the G100. Its a great colour combo. A darker blue than some of the stock photos suggest and the yellow writing really sets it off.
Only £45 brand new from amazon aswell!