A nice touch is how the unbranded brand uses a bright indicator LED, so you know at a glance when it's active.
Durable 20PCS DIN Rail Electromagnetic Relays – 10A 24VAC with Plug-in Design
The Formiden brand is right there on the relay, and that makes sorting through spares a little easier.
What stands out about the unbranded brand is the lack of logos, keeping the look consistent with other anonymous hardware.
You will find that the unbranded design things basic, which makes troubleshooting quick and stress-free for most setups.