I believe the BO105 limitations are the same as the BK 117 :
Plus 3.5 g
Minus 1
Somewhat bigger than most helos at +2.7 and +0.5
The minus 1g is to cover big pushovers during terrain flight.
The German army used to regularly do a roll-over and pull-through from 2000' or less. May have even been 1000', it was hard to understand der Cherman Tezt Bilot ve vlew vit. But a -1g bunt raises a lot of dust off the floor and into the eyes - gotta keep a clean house.