At first glance, running 2nd being beaten by 5 len is probably the higher rating performance. A 5 length winner generally means a high rating race for its class, imo. It would depend on the quality of the horses in both races however.

Having said that, they are both very similar aren't they? Beaten 4 lengths , then 5 lengths in same grade. One rating figure could fit both performances here.

I tend to grade horses now in blocks of 3 pts; eg 100, 97, 94, 91, 88 etc. based on their recent ratings.