I’ve had the Xtar Wp2 for past five yrs or so. No problems. Of course I never tried over dis-charging it with a high drain 2+ amp Ipad or similar. It has run my Iphone periodically with no problems.
I have that charger as well. Never any problems other than it won’t reset a tripped protection circuit. But that’s not a safety issue. My VP1 and 2’s do reset tripped battery protection circuits though…