The quest for a good switch is one of the biggest parts to any mod. The ones on the Puffer and I believe the Chuck are good switches for what they are, but they have a big issue with quality control.
http://www.madvapes.com/Push-Button-Switch--Black_p_2089.html
For ten switches that work flawlessly you will find two that are destine to break quickly. I found by checking the switches action you can often find the bad ones but often is not good enough. The problem is manufacturing defects from the switch builder.
One interesting thing is that the black ones fail more often than the colored ones. They also have more brittle leads.
I agree on the
C&K switches, they are far better but they cost a good deal more. I feel the cost is worth it and will most likely be moving towards using similar switches in all my non mechanical mods. Madvapes also has a
3a switch from NKK that is a tad large but looks promising. I have not tested that one yet so I can not vouch for it but I have several on order.
The most reliable switches I have found are
touch switches but finding a small one is tough, most common over the shelf ones only get down to 19mm. If you can fit it they are a very attractive option.