Tricky one...
I would say Etek, just for pure reliability, the Mini is super quiet, very little kick and its very air friendly. Etek is equally as fast, bit louder and more kick but you know its not gonna die and your not gonna loose it in the grass.
Size- Etek feels like a marker should in terms of size and ergonomics where as the mini is too tight and cause of this I keep turning my pulse off
Etek wins!
Ease of use- Both are very similar to program and operate, but the mini does not come with an air on/off so getting bottles off is a pain and it aint nice to your Bottle threads.
Etek wins!
For me I would go for the Etek. Its the sex!