Which is the better trade in program?

I one of those unlucky guys who thought we won't need an iPhone X and bought an iPhone 8 plus. So after using the 8 plus for a couple of months and watching friends use the X. I've decided to sell this one and move up to the iPhone X. It is not because the iPhone 8plus performs badly. It is not nearly unique as the iPhone X.

Anyway, I don't want the hassle of selling the phone on craigslist or something. So I am looking for a trade-in program. My options include Apple's own iPhone trade-in program and this phone trade-in program. Which one do you think is better? It is not about making more money. I want to sell my phone to a company who cares about the program and gives great customer service. I hope you guys can help me with this.