Yes and no. They’ve been working pretty consistently for me, but still had a recent problem with a bad mag strip, and then the replacement card was drained before I even got it in the mail. So yeah they’re working decently, but still have occasional issues.
What I have done before is at a grocery store is open the card package, call the USB customer service agent and ask if the card has had any pending charges on it before I bought it. If it did have any attempted charges on it, the card would be instantly blocked as soon as it was activated. When the agent gave me the go ahead, I would then purchase the card at self checkout which it allows. I hope USB has changed their card switching scheme to utilize 8-12 digit changes instead of just the last 4 digit changes.