I have and use the MLCS extender. It extends the bit a little too far
for my liking, but until I picked up a Jacobs Power Collet, it was one
of the 1 or 2 solutions for a plunge router out there (the Jacobs Power
Collet was on closeout). The Power Collet appears to extend the bit a
perfect distance for my DW625, but I don't have any long term
experience. I say long term because the collet is a quick change
concept where you put the bit into the collet and push the outer ring
down and it "snaps" on the bit tightly. It is great for above the
table bit changes in seconds.
I did a search on the web and never found any real problem with the
design, but since it went out of production about 3 years or so ago, I
have not seen any recent posts either positive or negative. If anyone
has some knowledge about its long term performance, please let me know.
I can understand why it went out of favor for handheld use. It
demanded extenders for the baseplate of the router and I am sure that
was not acceptable to the majority of router owners.