The switch issue has become a more important issue for me when it comes to buying or using a flashlight. My desire if for the light to be as easy and as simple to use as possible. Every time you add a strobe, SOS, etc. setting you need a more complicated switch system. You end up with one tail button you need to tap several times to get the result you want. Or, a combination of tail cap, side button. Or even a twisty head switch. I'll explain my thoughts. This is easy for me because I only use 3 lights. I'll list them and my pro's and con's. Having mentioned "con's" they are all great and the worst switch system I can live with easily.
First light (and the one that prompted this post): Fenix LD01 and Fenix LD02. I had a LD01 that I loved and was by far my most often used. I could walk my dog at night with it using a 16 foot retractable leash. The LD01 uses only a twisty head. No "last setting memory". Low, med, bright settings is all you have. For a very small EDCf light this is the perfect light for me. Grab the light from my pocket and turn the head. The light came on at the medium setting and that was just what I wanted 90% of the time for a light this size. The LD01 uses one AAA battery. I carried that light for 2 or 3 years using the pocket clip. One day I needed it and it wasn't there. I'm sure I pulled something out of that pocket and the light by accident and it was gone. So I started shopping for another one and the LD01 was discontinued. My favorite option in the Fenix line was the LD02 but it uses the tail switch only. Using other lights with tail tapping I found they are ok once you get used to the strength needed to change the brightness while not accidentally turning it off. I looked on ebay for Fenix LD01 lights and when I found a new one they were around $80. I think the price jumped from around $30 to $80 was because I bet they are in huge demand and will sell at that price if you want to wait to sell them "new". OTOH, if they are in such demand, why would Fenix discontinue that model??? What I love about the twisty head switch on a light this size is I turn it on and change settings if necessary with the light in the exact same position in my hand. Now I have the LD02 and after turning it on I reposition the light for use with the head between thumb and index finger. If I want to change settings I re-position the light putting my thumb on the tail switch. Hopefully, I change the setting without turning it off by accident.
My next favorite light is a Fenix PD32 (older model) which uses a tail switch to turn it on then a side switch to change settings. This allows me to change settings without changing the position of the light after it is turned on. And there is no needing to only press a button half way. This half way button push is one thing I'm not good at. Emotional flaw I'm sure.
Third favorite: Eagletac D25C2 mini. This uses only a twisty head like the LD01. But using 2 CR123A batteries it is twice the size of the LD01 or LD02 making it not my favorite as an EDC light. Of course this is a personal need thing since my most often need for a flash light is for a low brightness. If I needed more than 70 lumens more often the lights with 2 CR123 batteries are fine but I'll take a smaller size when I can.
Personal note: I haven't owned a lot of lights but of every single one I've bought and used I have NEVER used the strobe, SOS or any other setting than a different brightness. SOS is the only one I see a use for in case you are lost in the rocky mountains. That setting is like insurance. Hope you never need it but NEED it when you NEED it.
These are my thoughts. Not complaints really. Since I only use 3 lights (2 really) I'm used to the switches. For those who use many different lights, different switch systems can get confusing since you need to remember which system you have in your hand. What it boils down to for me is "ease of use".
Good luck and happy seeing in the dark,
Jack