I've no firsthand experiance with them but have been in contact with a fellow who used them to build a small barn (he's got a thread on the project in another forum). The drill guide they sell is well made and makes hole alignment practically a no brainer.
The general concensus is that a good timber framer can produce most joinery fast enough (with a mix of power and traditional hand tools) to be more economical. If you've already invested in a chain mortiser you can definately make M&T joints more economically.
The Timberlinx system will simplify tension joints and complex intersections of multiple timbers, so in these joints it tends to be more economical. BUT... these are the fun (challenging) joints to layout and cut. To my mind the satifaction of a properly executed joint (espescially one I've just attempted for the first time)is far more valuable than time savings, however my focus isn't getting as many frames out the door/year as possible.
