Normally I fly the Centurion, but I thought I'd mix it up and try the Orion.

With a lvl 5 Engine Upgrade I had a bit of a conundrum on shields.

Is lvl 5 Shield Generator better than lvl 4 Shield Generator when I turn off a level of shields (with the 'S' key)? I kind of like the idea of having a lvl 5 in case I really need the survivability, but running with it down a tier most of the time. However since the whole S/Shift+S increment change only has 3 levels, I'm not sure if by turning it down "one" it's actually going from lvl 5 to lvl 3?

Hope that makes sense, I don't know the terms and I can't find much help in the manual or playtester's guide.

My impression was no. It felt more than your shield was becoming level 2/3*5. I think it made the game harder to have level 5 shields and Shift-S down. Either stay with level 4 guns'a'blazing non-stop or install a level 5 shield and pick your shots. I installed level 5 shields for the final battle, as your Steltek gun is pre-supercharged and you only get a couple shots before you lose that.

If you're trying to use more expensive weaponry than Tachyon guns with level 5 shields, you're going to have a difficult time. Playing through the expansion, Righteous Fire, I topped out with Tachyon guns, level 7 engines and level 5 shields. You get one stupid mistake with those shields (full afterburners into an asteroid with only minor cosmetic armor damage - which is great cause you can get through the game quickly on constant afterburners). You can take out a Retro or Hunter every couple seconds. It worked so well I never bothered to try to upgrade to level 6 shields.

There's also the Privateer Playtesting Guide in the downloadable extras. After I finished RF I was searching to find out if you can recover your stolen Steltek gun and remount it. On page 58, it says the ideal shield & engine combination is level 4 and 5, respectively.

Thanks for the reply.

And yeah after some testing, my gut feeling, and your comments I feel like lvl 5 shield really isn't the way to go in the base game. lvl 4 just gives so much more energy, and the shift+s downgrade from lvl 5 to an unknown amount certainly seems lower than 4.

Sometimes I wish Privateer provided just a feeeeew more hard numbers and detailed information in game.

There is, however, one moment, when level 5 shields on Orion are handy...
you guessed it - it is the final boss battle. Orion with level 5 shields (and full armor) is the only ship available to player, which can survive direct hit from the drone thus enabling even less skilled players to survive that battle.