Link: Learn more about the United Quest Card
Let's not kid ourselves about $1 in United TravelBank is worth $1, especially when that credit expires more quickly. When you use TravelBank credit to purchase a ticket, you don't get any bonuses or travel protections that you'd otherwise get if you had paid with an appropriate credit card. You'd also give up opportunities for flying on other airlines even when they're more convenient or more rewarding.
A discount of 10k miles also isn't equivalent to getting 10k miles. Again, the discount can expire, and you may have to give up other opportunities in order to fly United. It certainly isn't worth $150, as you seem to suggest.
@ Tony -- TravelBank credit is valid for one year. Sure, if you don't spend at least $200 per year on United, then this card absolutely isn't for you (and I think I made the point that this card is for those who fly United with some frequency). But that's not exactly a big spending requirement to reach.
Regarding travel protection, with most cards you only have to pay for a portion of your ticket with the card to unlock those perks. So if a ticket costs $210, you could use $200 in TravelBank credit, and charge $10 to a card with good coverage.
Tony, each of the United cards with sign-up-bonuses are worth it for the SUB, alone. While blogs need to present these as ‘keepers’ (so as to not upset Chase or United), let’s be clear, if you can create a SUB-ladder, rotate through United Explorer, Quest, and Club cards, each, every 24 months, you’ll do just fine, regardless of the underlying benefits of each product.