Correct, a push on momentary. Standard clickies offer this.
The surefire clickie's are fragile and i've seen multiple failures. A friend of mine had an e-series light and went through 3 tailcaps in a manner of weeks, one cap failed within minutes of installation. Until i'm satisfied that surefire has addressed those issues, they're out of the running.
Secondly, i prefer the "straight tube" design for this light as it would allow more carry options.
The Surefire L1's tailcap is not a clicky. It is a two stage LOW/HIGH push for momentary, twist for constant on tailcap assembly. While I do prefer the standard SF click-on tailcaps (like the Z49) for my duty lights as they have proven themselves to be 100% reliable over many years of service for ME, the tailcap on the L1 is an excellent choice for tactical applications, and has also proven itself to be reliable on other Surefire models over the years. Here is a interactive from SF's website to clarify the operation of the L1's switch:
http://www.surefire.com/maxexp/main/co_disp/displ/pgname/lightL1/strfnbr/6
The new switch assembly that will be debuting in the yet to be released E1B "Backup" is just that, a completely new design from Surefire, so its durability/reliability is yet to be seen.
Yes, there was an issue with the E series clicky tailcaps in the past, but it has since been rectified from all reports.
While clicky tailcaps do have more things that can go bad on them, as far as a
rear/tailcap mounted click-on switch goes, Surefire is the most reliable currently available in this particular configuration. The Gladius also had some serious issues with their tailcaps on the first few runs that has since been completely rectified as well. Many people on this forum like to bring up old, resolved issues in an attempt to smear Surefire and others reputations. (Not saying this is your intent at all, as your experience is YOUR experience) Anytime clicky tailcaps come up, you will find that the same people tend to throw the since resolved E-series tailcap failures into the pot to stir things up.
If the durability of clicky tailcaps is a big concern of yours, I suggest you avoid them completely as the Chinese light companies issues will only add to your concerns. The NON-clicky tailcap assemblies on Surefire lights such a the L1, L2 etc. are as solid & reliable as can be.