Mike,

You are spot on with your first point. If you can use 2½D strategies, do so. It might take longer to program or be a little more involved, but the machining will be far more efficient.

In your second point, yes, HSS & HSM are designed to do the same work but HSM is more efficient in terms of programming input. However HSS will more than likely produce a more aesthetically pleasing part (presuming the programmer knows what he is doing .

As I said in my earlier post, I use both but far more HSM and HSR than HSS. I look on HSS as the 3 axis version of SolidCAM's 5 axis machining module - in fact except for the tool axis control element the way geometry is defined is almost identical. Sometimes using HSM gives you a tool path that will result in excessive chatter or aggressive plunging or some other undesirable condition - that is when I use HSS.