Tirzepatide is tirzepatide. With Tirz there's no 'better'. To me, 'better quality' comes down to:
1. lower risk (US shipping, test results, a bank of reviews from verified previous buyers who were happy, etc.)
2. ease of purchase (crypto has stayed out of my buying in the 1.4 years I've been going grey)
3. a guarantee, plus a reputation for actually honouring it
4. staying power in the market
5. past deep-dive test results with no failures (over and above the usual identification, concentration and purity)
And sitting behind all of that is 6. pricing
Some Uther survo came my way through a group buy and it's what I own and pin, happily. Pricing played a part. Mostly, though, I'm a Nexa girl.