I’ve made 2 purchases from QSC.
Purchase 1 was an August T15 GB, paid with credit card via Wise. Bella was my salesperson - quick response via email, answered questions. I did not get a tracking number. I was a bit inpatient. Order arrived in 3 weeks, free shipping, 3rd party testing was included in GB price. Purity/fill guaranteed and reship included.
Purchase 2 was a Labor Day T30 GB, paid with debit card via Wise. Irene was salesperson - quick response via email, tracking sent in 7 days, arrived in 3 weeks, free shipping, 3rd party testing included in GB price. Purity/fill guaranteed and reship included.
I have looked at several QSC “promos” but they seem to be what’s left on the shelf with no guarantee for purity/fill so I’ve stayed away.
I did consider Amopure initially but price was higher than QSC GB price. I found more info on QSC’s history/track record than Amo and it appeared to me that QSC had overcome their underfill problems.