I have both Fenix E21 and LD20 (premium R5 version). I like the E21 for simplicity, and it has Energizer L91 in it, stored in my car as a simple on/off flashlight with 2 modes. Don't have to explain to others on how to use it if they need to borrow it.
I like the LD20, and I use it mostly as my indoor flashlight, as in, i like the low modes on it, and I can switch to brighter modes as i need to. Coupled with diffuser tips, it's a great indoor light (for my use). The E21 was too bright for me to use indoors after my eyes have settled to the lighting inside (for close range usage).
About the donut holes, yes it's there. I got annoyed at first, but gotten used to it. 1
Another thing to note bout the LD20 (at least for my R5 version), is the battery type. I used Energizer L91 (1.7V) with it when i first got it, but realized the low-mode was gone. It's like medium/medium-high/high.
Read more on CPF and found out the higher voltages affected the low output, so I ended up using Eneloops (1.2V) and it's fine since. I got the desired low/medium/high modes.