I really like those cells and they would be well suited for a low-load UPS with the BMS you found. I considered them for a powerwall project but this being India, the really good deal is in used LFP cells - they’re usually priced at under 2000 for a 80Ah cell! (India has pretty great second-hand pricing for basically everything).
I’ve been hooking up my series-connected-cells-without-a-bms to the Inverter during extended power cuts and recharging each cell up manually afterward, LFP’s efficiency is very impressive.
Most basic BMSs have a cut-off at 3.75V so those should be avoided, the one you found has the proper over-voltage and over-discharge thresholds.
Yes, this is the one drawback of using a LFP pack with any UPS/Inverter regardless of whether it was made for LA or Lithium batteries. 1C is usually the maximum, with some (older) packs allowing peaks at 3C to 5C.
However, some people on youtube have noticed some BMSs will block the UPS from powering on after the pack is drained completely. They got around this by installing a push button that’ll bypass the BMS wiring to allow the UPS to sense that there’s a battery so that it will power on. This is for UPS models that need a battery to turn on even if they’re connected to the mains ac. Most UPSs will let you turn on without a battery with a long press of the power button.