Now we're getting deep into this dissertation!
I don't know what most people do with twin engine models do but for several of mine I have run CW/CCW and CW/CW and had little to no discernible change in flight characteristics under basic flying conditions... Others of mine, like I said, seem to be a bit more sensitive. (and those tend to be ones that rely on differential thrust to turn) I agree with
@Wildthing that most twins with counter props run the CCW on the right wing but I have some little scratch builds that I had to switch from that rule to encourage some "rolling" in the turns:
This plane flies with elevator and differential thrust only and breaks the rule by having the CCW on the left wing
I know that "Full Scale" aviation is about 50/50 for CW/CCW twin engine planes for a lot of reasons. A lot of WWII planes run all the engines the same way so the spare parts are always universal which is a thought to keep in mine when at the field. If you have all CW engines no need to worry about double sets of props! A lot of smaller twin engine "full scale" planes run with motors that spin the same way for the same reasons, Cost and Simplicity. Some planes, like the Comanche, had options for a CCW engine on the right wing but they were less common than the CW/CW birds.
Here's a CW/CCW Comanche with props arranged as
@Wildthing noted and one with CW/CW:
SO LONG STORY, SHORT...
It probably doesn't matter what way you run them! Odds are it will not be a significant difference for you one way or the other but my $0.02 would be in agreement with Wildthing on this one and say that the best possible arrangement is to have CW/CCW.
All that rambling and probably the only significantly useful piece I have to add is from a bit of experience I've picked up along the way. If you're using a threaded prop shaft motor, or prop shaft adapter, don't sweat running a CW motor CCW, just make sure your nut is good and tight... (or as we like to say in my German heavy neck of the woods... GuttenTite!) The only time you will lose a nut is when you have a prop strike at power and then the likely outcome is that the prop nut will loosen, your prop will come off, and nothing will be broken! So its a win win! lol
And to make sure this isn't a COMPLETE hijack of the Lidl thread we are on....
I got this in the mail today!
Its my Amazon "Lidl" knockoff!
Looks quite promising, might even say the foam is a bit more dense than the Banggood one I've been flying so thats a good sign!