I have not tested the size of blueprints, but I have tested performance agaisnt a simple condition, 3 integers a, b ,c… Checked for equality, a == b AND b == c, with normal nodes… Then with math expression (a == b) && (b == c)… Surprisingly the math expression node was faster:
Both scenarios were tested in 4.17.2 in an empty map with just the code actor, in a loop with 100.000 (0-99999) loops:
Scenario 1 (1 condition check per loop):
-RegularNodes : 0.720 ± 0.015
-MathExpression: 0.650 ± 0.015
Scenario 2 (50 condition checks per loop):
-RegularNodes: 2.694 ± 0.028
-MathExpression: 2.413 ± 0.023
Math for the time : ((Highest+Lowest) / 2) ± ((Highest-Lowest) / 2)
Pool: 50 times for each scenario