Anyone else finding cheap AliExpress BMS units are actually decent these days?

Picked up a 4S 100A BMS from AliExpress last month for about £8.50 delivered — JBD/Xiaoxiang branded, the kind you can hook up to a Bluetooth app and actually see what's going on with each cell. Was fully expecting it to be a disaster but honestly it's been running my 280Ah LiFePO4 bank without a hiccup for six weeks now. Balance current is only around 60mA which is slow, but it's doing the job.

Previously I'd have told anyone to just spend the extra on a Daly or even stretch to an Overkill Solar unit, but the gap seems to be closing. The cell voltage readings match my Juntek meter within about 5mV, over-current protection tripped correctly when I accidentally shorted a lead (don't ask), and the low-temp cutoff kicked in properly during that cold snap we had in February. Can't really argue with that for under a tenner.

Curious whether others have had similar experiences, or if I've just got lucky with a good batch. Anyone running these longer term — say 12 months or more — and how are they holding up? Also wondering if the higher current versions (150A, 200A) are equally reliable or if that's where it starts to fall apart.

@SilverSpanner JBD units are genuinely solid for the money — been running one in my cabin setup for nearly two years without a hiccup. The Bluetooth app is surprisingly decent once you wrestle it into English.

However. And this is a big however. I've also had one arrive completely dead, and another that decided 3.65V was a perfectly acceptable resting voltage for a cell. So the quality lottery is real.

My current approach: buy two, test both, keep one as a spare. At £8.50 each you're still laughing compared to a branded unit.

The genuine JBD ones (look for the actual JBD PCB markings) seem consistently better than the random clones wearing the same branding. Fogstar apparently use a variant in some builds, which tells you something about the ceiling on these things.

Really good timing on this thread — I've just been weighing up the same thing for a 280Ah build I'm putting together. @CamperSam two years is reassuring to hear, that's proper real-world validation rather than just bench testing.

One thing I'd add is that the Bluetooth monitoring side of the JBD units is genuinely useful beyond just peace of mind — being able to check cell balance deviation remotely has saved me catching a dodgy cell early on an older pack I was reusing. Worth calibrating the capacity reading properly when you first set it up though, mine was about 8% out of the box.

Only concern I'd raise is that quality control can be inconsistent across batches, so buying from a seller with decent feedback specifically on that BMS model matters more than just overall store rating.