Replying to myself...
I've been using the SL Macrostream now for about 3 years. It is my go-to backup work light. I've used it on the brim of my hat while working in crawl spaces and for outside work (landscaping and snow removal). I like the fact that I can recharge it in the care without taking the battery out. It uses a mechanical switch.
Batteries... the Macrostream uses a 14500 rewrapped so that the positive and negative present on the positive side. You can replace it with a 14500, but will lose the charging capability. It is the same for the Microstream (10440). Unfortunately, the pocket clip makes it a pain to swap batteries, but I only did this to see if it worked, and after three years as a go-to EDC I have no problems ponying up th $10+ dollars for a replacement SL brand 14500.
The beam profile is like many 14500 lights... floody. In fact, I'm contemplating buying a second instead of just a battery, and seeing if I can swap the LED for something with a little more throw fo I'll have the original for work, and a throwier one for general EDC... I'm contemplating the same thing for the Microstream in Coyote. Right now, my go-to 14500 for spotting at range is either an Eagletac Clicky with an Osram culpm1.tg (reverse clicky) or the Weltool TC Pro with the Cree XP-P (forward clicky). However, they are not as nice for closer task related work duties when I might be recharging on the job-site or in car (the ET and WT require the batteries to be take out to charge).
I really would love for SL to make a "tac" version with a slide usb port (so the head doesn't move), crenalated bezel, and 10 tap programing.