Well I ride every day. Whatever the weather and I've found that the 520 seems to wear pretty quick. So I need longevity.
My first chain went pretty quickly (~19000 km). After I replaced it, I installed an automatic oiler.
I was trying to clean and lube the old chain every week. Never done either on the new one. It's been about 16000km and it's fine. Didn't even adjust it until around 13000km. OTOH most of those first 13000km were dry-season, and that probably won't wear the chain as much.
I have the PD Oiler, and I'd recommend it, although I'm sure there are other good products as well.
Difference between a 530 and a 520 is the chain width between the inner plates of the chain.
Both chains measure 5/8 inches between pins but a width of a 520 is 1/4 inch and 530 3/8 inch. IMHO, best to stick with the oem spec. if need to upgrade is to get a X-Ring 520 chain. Agreed a scottoiler or a good chain oiler would prolong the chain life longer than not with one.
The original is an EK 520 MVXL1 (OEM type) X-ring chain. Mine was bad from the start and I finally replaced it at 2600 miles... My replacement DID 520VM (now 520 VX2) X-ring chain is absolutely excellent now with about 7000 miles on it so far.
You can do even better if you go with the top of the line from EK, DID, Tsubaki, Regina or RK... The strongest are EK 520 ZZZ, ZVX and MVXZ, but they're considerably heavier than DID 520 ZVM-X and VX2.
My original stock chain has over 17,000 miles (27,000 km) on it, and it's hardly worn at all. I've adjusted the axel out one hash mark from when it was new. I just lube with the blue Dupont Teflon Spray every 400 to 600 miles or so. I lube more often when I ride in the rain.
Do you do a lot of off road riding and get alot of grit on the chain? Do you adjust the chain tension per the manual?