This review was sponsored by flashlightgo from where I got the flashlight for free in return for this review. Thank you very much!
The full review is available here
English review at BLF
German review at my website
Summary
As long as you ignore the term "tactical" in the product description, the Acebeam TAC AA is a nice EDC flashlight. On the larger side for a AA flashlight, but just the right size for a comfortable grip. The Nichia 519A with its lovely tint and high CRI will make you happy. The universal beam is great for EDC use and comes with good throw for a light of this size. Build quality is superb and it feels very robust.
Unfortunately the driver is on a different level: Simple brightness regulation using PWM and the modes are messed up when using a NiMH battery. A real shame, because the TAC AA would have been a very nice, simple AA flashlight for family and friends. I wonder why Acebeam didn't use a better driver.
Overall the Acebeam TAC AA struggles to stand out against other less expensive flashlights. Yet it is a good option if you need support for Li-ion and NiMH batteries, as long as you don't miss the medium mode with NiMH. There aren't many other candidates with similar features.
Which input lag do you mean? When it press the switch, my light turns on immediately.
Maybe I have a different revision than you. Both of my Tac AA and Rider RX have probably 150-250ms of lag after clicking the switch to when the light actually emits light.