I really like these Dewalt guide rail clamps
http://www.amazon.com/DEWALT-DWS5026-TrackSaw-Track-Clamps/dp/B001J31PJM/ref=sr_1_1?ie=UTF8&qid=1404101512&sr=8-1&keywords=Dewalt+track+clamp
They do a great job keeping the guide rail securely in place and offer easy to use, one handed operation
I do have a home made MFT with aluminum extrusions from 8020. I did have to spend some time with a metal file working on the part of the clam that slides in the t-slot before it would work smoothly in the 8020 extrusions. i also had to do the same with my Festool clamps before they would work with the 8020 extrusions.
Finally, be aware that the clamps won't slide into the holes in an MFT top.
Jay
http://www.amazon.com/DEWALT-DWS5026-TrackSaw-Track-Clamps/dp/B001J31PJM/ref=sr_1_1?ie=UTF8&qid=1404101512&sr=8-1&keywords=Dewalt+track+clamp
They do a great job keeping the guide rail securely in place and offer easy to use, one handed operation
I do have a home made MFT with aluminum extrusions from 8020. I did have to spend some time with a metal file working on the part of the clam that slides in the t-slot before it would work smoothly in the 8020 extrusions. i also had to do the same with my Festool clamps before they would work with the 8020 extrusions.
Finally, be aware that the clamps won't slide into the holes in an MFT top.
Jay