My RazoRock ECO razor arrived yesterday from Shaving Station, I shaved with it this morning.
Physically it's the same as a RazoRock Hawk as it can be. The head has the same shape and style , shave angle is the same as far as I can tell. The only differences are to accommodate the different sized and shaped blade. The blade is held in position very well (unlike my Focus R48) and is as easy to load as the Hawk . Four small posts hold the blade firmly in position, someone posted a pic earlier in the thread. I can't see the half DE blade being able to flex in there at all.
In my opinion SE razors need a sharper blade than DE razors to function well. As a result SE blades tend to be sharper than DE blades (big generalisation!). I believe that DE blades can be as sharp as SE blades, but I also believe that SE blades hold their edge longer because they are made of thicker steel. I suspect this makes them easier to put a sharp edge on as well. It's far easier to get a good edge on a wood plane blade than a pen knife blade.
For my first shave I used my go to blade for DE razors a Polsilver Super Irdium, It wasn't as smooth as a Schick Proline P30 in my Hawk, but I think that was a sharpness issue. I'm thinking of changing to a feather DE blade for my next shave. It's early days yet but so far I'm happy with it. I'll post more as I use it more.