To Air or Not to Air.....

In January we're printing/posting responses to the reader question we ran in the November issue. We're getting responses on both sides of this, so I'd like to hear more from some of you. If you haven't seen it:
"We’ve always used servomotors to translate rotary motion to linear motion via slides, ball screws and other mechanical components. A necessary upgrade for better reliability and versatility is at hand, and contrary to a lot of market conversation, a more direct pneumatic solution looks promising because of its integration with electronics, manifolds and other controls. Most our our customers have compressed air systems. 
But there are equally promising integrated linear motor packages that might save space, and be an almost plug-and-play upgrade that our customers might accept. 
So far, there doesn’t look like there’s a big cost differential in either case. We’ll get an upgrade either way, but is there a prevailing opinion about best bang for the buck here? "