SteamVR and in game PD multiply. There is no difference in Quality.
If you run SteamVR at 200% and PD of 1.0 in game, you are getting a PD of 1.4 in game.
If you run SteamVR at 100% and PD of 1.4 in game, you are getting a PD of 1.4
If you run SteamVR at 150% and PD of 1.0 in game, you are getting approx. PD of 1.2-1.3
Point being, it is easier to grasp the percentages if you turn SteamVR to 100, and just use the in game.
Again, with the Odyssey+, any PD over 1.5 you will lose range in your ability to spot. Keep that in mind. Also, anything over 1.5, and the cockpit will gradually become fuzzier.