After letting the oil drain out of the Victory all night, it was time to refill the beast. It takes 20/40 fully synthetic oil, which is not the most common of oils here in the UK. Most people seem to run them on 10/40 fully synthetic or 20/50 fully synthetic (as per the Victory forums). All of these options are more than acceptable accross the likely UK tempreture range. I've gone with a 15/50 after a good few recommendations from fellow Europeans, again it's well within the likely tempreture operating range. The original oil filters are getting hard to come by too as Victory's are no longer made, so I opted for a K&N item. The beauty with the K&N is it comes with a 17mm nut on the end of the filter to make it easy to remove if it's being a bit stubborn. All filled up, I just need to pop a few miles on and recheck it.
After having a good sift through the oil that came out, it wasn't as bad as I had feared. No metallic particles (hooray) and not as lumpy as I first thought, it was just well due for a change. The bike sounds as sweet as a nut now and idles with a lovely burble. Happy. I'll still change it again soon, purely as precautionary overkill.