For several months now I have been using the Musclechuck on my Porter Cable 7518 motor in my CNC Router. The chuck has worked flawlessly and it a great improvement over the old chucks that require two wrenches and two hands to install and remove router bits. This chuck is available on Amazon for a variety of routers, the cost seems to run between 70 to 100 dollars (US) depending on the router model it fits. All that is required to change router bits is one hex wrench.
The Musclechuck natively accepts 1/2" bits, for smaller bit diameters you purchase collets. The 1/4" collet is 35 dollars on Amazon. Honestly I believe that the Musclechuck is now a mandatory accessory for my router table and hand held routers in my shop. They are a bit pricey but worth every penny for any router motor that's used frequently and bit changes are made often. On my CNC Router bit changes are frequent so the convenience is well worth the cost of the chuck.
I purchased the 3/8", 1/4" and 1/8" collets with my Muclechuck and a Reid T handle hex wrench that has hardened hex ends so it should last a very long time.