Drilling horizontally in calcareous sandstone and in a concrete wall with 6, 8 and 10 mm was super easy. The drill fall almost in the holes, simple is almost not.
Working overhead despite The 3.7 kg, not "heavy", the drill (8 and 10 mm) went into the concrete floor as in the proverbial butter.
Although the UHE 2850 is not exactly a bargain, there are still a buy recommendation from me.