Out of all the fast food joints I've visited, mcdonalds was probably the one I went to the most during my lifetime. As a matter of fact, I conveniently live right down the street from one.

My mom is a big fan of Wendy's so if we go out to a fast food place (with my parents) then we usually go there. Even when it's not with my parents we tend to go there a fair bit.

Or McDonalds. My kids really like McDonalds as well. I don't love it but they do and I can put up with it. It's not nearly as good as it was when I was younger.

Usually Burger King. I love Burger King. If not Burger King then definatly Mcdonalds.

Very unsure about this one. For the longest it was McDonald's but, their food is so unhealthy I have really stopped eating there. I am between Burger King and Wendy's which I am also going to be cutting off as well. Definitely no Taco Bell or Chili's

The answer for me is easily Wendy's. I go there once a week to get my usual Baconator with medium fries and a medium Vanilla Coke. No other fast food restaurant is as delicious as Wendy's in my opinion.

The one that I go to the most of all of them has to be Taco bell, I just LOVE their food, and I'm going there today too. Sometimes I go to Burger King and Wendys, and that's about all of the ones that I go to, I rarely go to McDonalds or any other places.

I actually don't eat fast food as much as I used to anymore. The most common place I go to is Sibylla. Don't think it exists in the US but it's essentially similar to Mc Donalds and Burger King which we also have. Except in stead of just burgers it also sells hot dogs. The reason I go there is less because it's the place with the best tasting food and more because it's the only major fast food restaurant that's close by. Just down two streets from where I live.

Otherwise my favorite is probably Burger King because of their chicken nuggets and milkshakes. I don't really like McDonalds anymore and pretty much never go there if I have a choice in the matter. The other options in the thread seem more US exclusive (or at least aren't very commonly found here).

Wendy's all day every day. Nobody has anything that compares with their Spicy Chicken Sandwich or The Baconator. And their Frosty's are amazing as well. I could eat those for every meal and (regardless of weight gain) be a very happy camper.
A close 2nd for me would be Arby's, if only for their Beef 'n Cheddar sandwiches. I love me some beef n cheddar to no end.

Living down south I've got to go with Jack in the box.  The other options on this list I ate when I lived in the northeast, but I vastly prefer the buttery rolls and greasy curly fries from JITB.  While I'm speaking them into existence on this thread I ordered 14 of there tacos on a fast food binge last month.  I'm not proud of it, but they were super good and cheap to boot!!  Luckily I have a crazy fast metabolism, I don't gain weight no matter how much I eat. 

I am actually more a part of the In & Out crowd, but seeing as that isn't an option in the poll, my second choice would have to be McDonald's. My family and I used to go through their drive-thru a lot when we were on the road or just randomly one weekend when someone craved a Big Mac. I remember ordering the Big N' Tasty, which they don't even make anymore XD

Honestly among all of the fast food places I've eaten at Taco Bell the most because for one they have a happy hour and it's my favorite place to eat Mexican food even though it's not considered Mexican. I still haven't tried their breakfast yet and I don't plan to do so because it doesn't look very appetizing. You wouldn't ever catch me eating McDonalds and I'm ashamed I actually ate there as a kid.

Final Weapon :   I honestly haven't had fast food in years, possibly even decades.  I'd rather eat a whole pack of margarine and wash it down with paint for all the good either of them would do for me.  I'm sure you have heard or even seen the McDonald's stories of how their food does not "go bad."  I am sure that most other places are the same with all of the chemicals and preservatives and plastics in them to keep them "fresh" for so long.  Don't get me wrong here, as that stuff tasted soooo good.  I loved McDonald's fish sandwiches and double cheese burgers, and their fries were the best...so salty. Taco Bell's double decker taco and their grilled stuffed burrito were all I ever ordered from them.  Wendy's Double bacon cheeseburger combo was really good and very filling.  Burgerking had some really tasty burgers, but I didn't really like their fries.  I have never been to a Checkers so I have nothing good or bad to say about them.  Sonic down here in Texas has some really good burgers too, and their half price drinks are a real deal maker in the summer time.  That's all I ever get from Sonic...a route 44, (that's a 44 oz huge drink) vanilla Dr. Pepper, but I rarely frequent the place.