Thank you for your input guys. So many conflicting opinions! Think I'll have to play it safe, sell it on and buy a brand new one. Bit gutted though tbh, its probably safe.
If you reset device and get new seed we can say that you are 99% sure that nothing bad will happen just because it is second hand device. But since it is not new device which comes directly from the manufacturer there is always at least a little doubt that something may not be as it should be.
When it comes to security of cryptocurrency even 1% chance that it may come to an undesirable event is too much, since this is hardware wallet and not crypto exchange where users have no choice but to risk much more. It's a good decision to buy brand new device, few bucks cheaper used device is just not worth it.