I had the same questions as you, but ended up going with a Nitecore. From what I've gathered, the LUC has a digital display which moniters the actual voltage and charge rate of the batteries, it has manual charge current settings, is newer to the market and is more expensive. Nitecore has been on the market for quite some time and has earned a solid reputation. I love my Nitecore, it charges fast and is self adjusting as far as the charge type and rate of the batteries being charged.
Both of them run an initial test on the batteries before the charge begins to make sure they are in good working order before they start charging, and both start with a heavy charge rate and taper down close to battery capacity, and then trickle charge when the battery is close to and at capacity to maintain 4.2 volts. Can't go wrong with either or.