What would be the faster Strida for a 1.70 m and 70 Kg guy with quite good muscle strength, the Strida MAS with 16 inch wheels and 2 gears or the Strida SX with 18 inch?
What about the upcoming Strida EVO 3 speed?
Can the maximum speeds be calculated somehow given these conditions, so a comparison can be made like for example: 0.9 (MAS), 1.0 (SX) and 1.1 (EVO)?
Hello fsiefken, welcome! 
This doesn’t help you further?
Gear ratios information about different models of Strida
Not really, you’d need to know your cadence exactly; but this is variable always depending on wind, surface, slope,…
http://sheldonbrown.com/gloss_ca-g.html#cadence
For me the fastest would be to upgrade the MAS wheel set to 18" and put Schwalbe Kojaks on it.
The SX is lighter than MAS so it may be faster.