It is very difficult to predict range. We have tested the mc-Mod120 extensively and in the field and we get 200 meter without a problem. But our office is in a rural area so the spectrum is very clean.
The best solution for your problem is to experiment a bit. Try to turn the device and keep it away from water, people (mostly water), metal, etc.

The first quarter of 2017 we will introduce a new Gateway (mc-Gate120) with an external PA/LNA that is much more sensitive and two antennas that can be switched on the fly.