Your comparing apples and oranges. In one corner, a Corvette, the other a Cavalier. Both get you from point a to point b, one gets you there faster and it's more of a chick magnet and costs more.
Seperate components has technical advantages. Less prone to castrophic failure, easier to spare for uptime. But the downside is more wiring and fab labor and total cost. There are other configurations, and as I've pointed out in a bunch of posts, this whole arena needs to be thought of as a system and designed and built that way. Putting a $150 drive and a $60 motor on one axis that moves 3" and has minor mechanical loads is just insane and such a waste.
Phil, Still too many interests, too many projects, and not enough time!!!!!!!!
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