Here's my honest review for 2014 of the United MileagePlus credit card program. Even if you only fly with them occasionally, as of July 2014, it's a good offer because of the benefits that come with it.

United Airlines Visa card
The latest iteration of the United Airlines United MileagePlus Explorer Card is fairly unique in the frequent flier co-brand market, as it provides a lot of opportunities for earning miles:
  • 30,000 bonus miles after you spend $1,000 in the first 3 months
  • 5,000 more bonus miles when you add an authorized user to your account and they make a purchase with the card during the first 3 months
  • 10,000 bonus miles every calendar year you spend at least $25,000 on your account
  • $0 intro annual fee for the first year, then $95.
When you tally up all these mileage bonuses it becomes clear that this card provides a lot of value (especially since it only requires 25,000 miles for a domestic roundtrip saver award ticket). This is significantly better than previous sign-up promotions Chase has offered with earlier version of this card.

Better Rewards Program
Thanks to the merger between United and Continental in 2012, United is now among the largest carriers in the world. This gives United Airlines some distinct advantages and benefits over many of the smaller airline frequent flier programs...
Reason #1 – Award Seat Availability
Nothing is more annoying than attempting to redeem miles, only to be prompted with that classic line "there are no reward seats available on this flight." Well you definitely won't have to worry about that problem with United because if a seat is available for sale, it can be yours at the Standard Award level. Pretty cool, huh? However, this new perk is reserved for cardmembers and Elite frequent fliers. So if you want to redeem your miles without blackout dates or restrictions, get the credit card!
Reason #2 – More Destinations
Being that you have almost 370 destinations across 6 continents, with nearly 5,600 daily flights, you are getting access to the world's most comprehensive airline network.
Reason #3 – The Star Alliance
You have the ability to earn and spend miles on the 27 Star Alliance partner airlines. Since Star Alliance is the biggest airline network, it's definitely the one you want access to.
Conclusion? Not only will you be earning an unlimited 2x miles on United flights and 1x on everything else, you will have lots of options when it comes time to spend them.

More Benefits
The predecessor credit cards (the Continental OnePass and United MileagePlus Visa) each had unique strengths, but many frequent fliers were skeptical how these two programs would be merged. Fortunately what ended up happening is Chase took the most popular benefits from each and incorporated them on this new United MileagePlus Explorer card. Then they even added new benefits on top of that. Review the perks for yourself...
MileagePlus Explorer vs. competition
  • First bag flies free
    You can check your first checked bag free, which equals a roundtrip savings of $50. On top of that, if a person is traveling with you under the same reservation, they also get their first bag free, which saves you another 50 bucks.
  • United Club Access
    This benefit gives you 2 one-time-use passes every year to visit the United Club (their airport lounges). Normally this would cost you $50/visit if you weren't flying with a first-class ticket. So the yearly value of just this benefit alone is up to $100.
  • Priority Boarding
    With this United Airlines card you will receive priority boarding on United flights.
  • Primary Rental Coverage
    Almost every credit card offers secondary coverage, but those plans kick in after your personal insurance pays out (so you still end up with a claim dinging your record). However what's so unique about this United Airlines card is that it offers a primary auto rental collision damage waiver, which means it pays out first. Aside from United-Continental, I can't think of any other airline branded card which provides this perk – and it's worth the price of admission all by itself, honestly. If you've ever had an accident in a rental car and had to file through your personal insurance you will know what I mean.
  • Travel and Shopping Benefits
    Coverage for trip delay, trip cancellation, lost/stolen luggage. On eligible items bought with the card you get purchase protection and price protection. There's also complimentary concierge service and a luxury hotels and resorts program which offers special pricing and perks at participating properties.
  • No Foreign Transaction Fees
    Previously this card (and most credit cards for that matter) charged a 3% fee. That equals $90 fee on $3,000 in foreign spending. But now you won't pay a dime with this one. If you travel overseas for work or vacation it is critical to avoid foreign transaction fees.
Are there any drawbacks?
So we've gone over the pros but how about the cons? Well, this United Airlines credit card review wouldn't be complete without going over the drawbacks too. Here's what I dislike...

The APR is 15.99% (Variable). This is actually on the lower side for an airlines reward card, but it still isn't low enough to use for carrying a balance long term, honestly. If you are someone who regularly carries a balance, either get a plain vanilla card from a credit union (because they're about the only places that offer low rate cards these days) or play the 0 percent balance transfer game to avoid interest.

Verdict?
The pros far outweigh the cons if you frequently fly United. Given the size of the airline post-merger, there's a good chance you might. And just to recap, what Chase is offering at the moment (as of July 2014) is by far the most lucrative deal I've seen from them in a very long time:
  • 30,000 bonus miles simply for making $1,000 in purchases during the first 3 months.
  • 5,000 additional bonus miles when you add an authorized user to your account and they make at least 1 purchase with the card during the first 3 months.
  • For each and every calendar year you spend at least $25k on your MileagePlus Explorer card, get a recurring annual spend bonus of 10,000 miles.
  • $0 intro annual fee for the first year, then $95.