I wear a pretty similar style to the one you're looking at and mine is 60% density. It's a bit if trial and error when it comes to getting the specs right but I reckon 60 would be a good starting point for you. 55 or lower could end up being too low. You can always pluck a few hairs, thin the system, or even use some hair removal cream which some guys do to lower the density but there is no way to increase the density once you've got it on your head so at this stage I'd be a bit cautious, go with around 60ish and see what it looks like.