I now use a mixture 75% Black and 25% Tough (mixture by weight). This was printed on the Form2 in a Black cartridge ie with Black settings. We call the mixture Blough. And it works quite well for us. We make precision engineering parts, that is parts for mechatronic, everything from rice grain size to golf ball size. Almost everything is printed in 25µm setting. Parts with Blough also have snap-in assembly constructs.
Blough prints very well at 25µm, has excellent detail, and is impact resistant, and is stiff enough for mechatronic prototypes. I don’t have too many problems with removing it from the platform; but I do use cans of cold air (<-20°C) to avoid problems - alot of the parts we make have details smaller than supports.
Blough is not smelly like Tough and I don't have an issue with post-curing the surface (as tough can have)
I will also try clear 75% + tough 25% and white 75% +tough 25%, but only because I have liters of white and clear which I do not like:
White (Ver2) is difficult to remove from the platform, brittle and you can print at 25µm.
Clear (Ver2 and Ver3) is too brittle. It gets more brittle and yellowish in the sun.
Comments about the other Materials:
Tough is too flexible for my liking, stinks and the dimensional stability isn't very good - parts come slightly warped, probably due to the low heat distortion and low elastic modulus.
Black is the better standard material, but is still too brittle.
The Durable that is coming out next year has a very very low flex modulus (I only have the current published values, obviously not tried it) and is extremely flexible, so I wonder what the difference between Flexible and Durable will be for practical purposes…