My faith in Rigol products has dropped quite a bit, and so I am indeed reconsidering any future Rigol purchases. However, this sort of stuff happens. Products are defective. These are entry level, tiny-profit-margin products, the low price comes from somewhere.
Life is too short to get emotionally upset over stuff like this. It is frustrating, the scope I paid for (which had only been on enough to use up half of the trial hours) is not doing me any good, it's on a FedEx truck.
However, I knew the Tequipment return policy going into this, so I am not upset. They did their part. When my DSA815-TG came from Tequipment and I discovered the display was defective, they exchanged it and paid return shipping. They did hold onto it for a week before shipping out a replacement, which I was not happy with, but when I complained they expedited the shipping.
Anyways, I digress... I'm just saying that Tequipment did their part and are following their stated policies. The way Tequipment can offer low prices, free shipping, and the EEVBlog discount is by maintaining policies like this. Extended return policies can be expensive when your profit margins are thin. If you wanted the option for an extended return policy, perhaps you could have found a vendor that would do so. But I would expect the price to be higher.
If anything, you should be upset with Rigol. It's their QA etc that failed you here.
Anyways, just my personal opinion.