Two other options since the vehicle is (I assume) out of warranty.
The good old standby Rotella T6. Does it carry the 502 spec? No. A3? No. Does it likely meet or exceed them. Definitely. The cSt @ 100 and HTHS specs certainly fall in line with what the VW 502 spec is designed around.
Also if you'd like to go with a lighter weight oil for some possible fuel economy improvment, Mobil 1 ESP 5w30 is a fine choice.
http://www.mobiloil.com/USA-English/MotorOil/Oils/Mobil_1_ESP_Formula_5W-30.aspx
http://www.mobil.com/USA-English/Lubes/PDS/GLXXENPVLMOMobil_1_ESP_Formula_5W-30.aspx
It doesn't carry the 502 spec and instead meets 504/507. However Mobil explicitly states that it will satisfy the requirements of the 502 spec (though they don't have official approval for that spec.)
HTHS of 3.58 with a vis of 12.1cSt @ 100deg which is certainly substantially "thinner" that the 502 spec Xw40s that typically are running at 14cSt or higher @ 100deg.
I've ran a 5w30 502 oil from Elf in my wife's 2.slow Golf before and there was an appreciable increase in fuel economy (and butt dyno readings as well).
Right now I'm running the "new" Edge w/ Syntec 5w30 (SN formulation) in my wife's 2.slow. I'm comfortable with the thinner non-spec oil because its been discussed at length on here and elsewhere that the 2slow is easy on the oil and some posters have show very good results using anything from high quality non-spec'd 5w30 syns to HDEO in these engines. The Edge still carries A1/B1, A5/B5, GF-5, Dexos, and all the other Ford, GM, and Chrysler specs which since I'm not doing extended drain intervals or flogging the car to death on the autobahn where a 40wt would be understandable.
I also have NEVER gone with the 10k mi / 12mo OCI VW recommends, preferring instead to just to a change every 6 months since she never puts more than 4000mi on in a 6mo period.
Regardless of what oil you choose, I would strongly suggest going the 6mo change route instead of pushing it out to a year.