I have had 3x Lii500. The IR in every one of them is useless. Otherwise a good charger. I use it often.
My Opus is a tad rough and variable for IR but serviceable. There is speculation that the pulse charging is not as good for cells, especially small ones. So far…no proof of that. My oldest and best charger uses pulse charging and I have cells over 10 years old still serviceable. The Opus is my most valuable charger.
There are extensive threads on both chargers with lots of opinions on both. HJK has reviews on both (see links above post).
Others that may be more accurate are 3-4x the price.
If IR is an important feature and you don’t want to spend like $90, the Opus is your only choice I know of. You can do IR without a charger but that’s another discussion.