Actually, I'm just going by second-hand knowledge. I may have misinterpreted what I was told once. Never mind me 
And I memories to the dark ages.

They had space ships, were incredibly techno-savvy and STILL debated as to intelligent or merely instinctive techno-builders. However, they were difficult to keep, inventing something to release themselves if in the mood, but could be found with Inquisitors.
If in an Imperial group, they could be annoying 'fiddling' with stuff, but tended to either make an object more aesthetically satisfying to the 'ape', or improved to god-like powers.
Still don't think of them as an 'army.'
Doug