If you are new to this world or prefer a reliable, moderate experience, these are likely the names you have heard of. They are the "Toyota" and "Honda" of the pouch world, reliable, everywhere, and consistent.
VELO (formerly Lyft in some markets) is arguably the most popular pouch in the UK. They are famous for their soft pouch material. If you have sensitive gums, VELO is often the safest bet. Their "Freeze" and "Ice Cool" flavours are industry standards. The nicotine delivery is incredibly linear; you know exactly what you are getting every time.
ZYN, on the other hand, often uses a slightly drier format. This is crucial to understand. A drier pouch means less drip (the liquid that runs down your throat), which some users prefer as it reduces throat irritation. However, a dry pouch takes longer to activate. You might put a ZYN in and feel nothing for two minutes, whereas a moist VELO hits almost instantly.
If you are looking for a starting point, browsing the Zyn nicotine pouches collection is a sensible move. They offer lower strengths that won't knock you off your feet, making them perfect for the office or social settings where you just want a subtle lift.