Pavane wrote:I have tried them in combat. I don't see any appreciable difference, so the additional cost sours them for me.
P.S.
I've started a new game, so I no longer have Blade engines. When I do, I will try an experiment. I will create two Spinal BR designs as similar as possible (with unique weaponry not used on other ship types): one Antimatter BR design and one Antimatter Blade design. My fleet will have two BR Carriers, one with each design. I will fight the same battle twice, but only launch one BR design in each battle. I can then note from the after-combat screen how much damage was inflicted by each design and how many survived.
I think this here is why the engine type doesn't seem to be doing it for you. As you mentioned before, the main advantage the blade\streak BR engine has is its improved speed and time on station but its weaker in a direct fight.
Wouldn't speed and time on station improve longer range BR options more? Try placing them on a Torpedo BR armed with one of the tracking torps such as Enveloping Antimatter. Due to how the AI works with them, they will fire their torpedo then flee any return fire, and having more speed means they'll be safer from said return fire due to putting more distance between them.