This is my first post ever, so here goes!

I just purchased an Excalibur Matrix 380 and I am VERY exited about this crossbow! Its my first crossbow ever and I have a few questions regarding shot placement & penetration.
I also own a 74 pound PSE Diablo, and hunt with it regularly. Generally shot placement with a bow needs to be precise. Normally behind the shoulder quartering away.
Does this rule apply to a crossbows as well? I have seen quite a few crossbow hunting video's where shots are taken directly on the shoulder, rather than behind the shoulder. Does this mean that crossbows are powerful enough to penetrate a animals shoulder bone with the bolt? The guys from "Hunting the backwoods" shooting Warthog, Impala and even Eland on the shoulder with the bolts passing clean thru. Must say I was impressed, but can this be done each and every time? The reason I ask is because most african animals vitals sit more towards the front, behind the shoulder.
Also, which broadheads are best for penetration?
Looking forward the replies...
Thanks,
Oelof