U4 exists and is sold here in individual quantities. 1A is a very cool white tint around 6500K and not what most people around here prefer. I have one of these, dedomed (which warms up the color temperature considerably) in a Fenix TK61.
I suppose if you’re chasing numbers, you should probably go for this. You might get another 30 lumens out of it. I don’t find chasing numbers you need instruments to detect all that entertaining anymore and would rather have something with good tint and color rendering.