Is the Fellow Opus grinder better than the Baratza Encore ESP?

Not universally. For most people choosing a budget grinder that can do espresso, I’d lean Baratza Encore ESP. It’s generally regarded as easier to use for espresso dialing, and Baratza has a strong reputation for serviceability and parts support.

That said, the two grinders are in the same general class and can both make good coffee, so the better choice depends on what you value most:

• Choose Baratza Encore ESP if you want a more straightforward espresso workflow and a grinder with a long track record.
• Choose Fellow Opus if you prefer its design, smaller footprint, and a more compact countertop presence.

I’d avoid claiming a huge gap in grind quality between them without testing side by side, because results can be very similar depending on the beans, recipe, and user workflow. Also, price and availability can vary by retailer and date, so it’s worth checking current listings before buying.