"Kitakata Ramen Bannai" or more simply Bannai Ramen is one of the largest ramen chains in the Kanto area, and they also have stores outside of it. It's a safe reliable choice when you want some basic good-tasting ramen quickly but don't want to go to one of the 390 yen stand-and-slurp places on the train platforms. The broth is a relatively clear pork and (slightly) fish-based broth, clearer and lighter to my taste than others but still salty, and the noodles themselves are a touch thicker, springier and wavier. For 150 yen extra you can get a large (o-mori) portion of noodles. The pork is good, cut into squares about the size of a matchbook, but the pieces generally have a large strip of clear delicate fat running through them. If this is not to your liking then it will melt into the soup if you leave it long enough.
The NishiGotanda Bannai Ramen is right next to a Tenkaippin branch as you can see from the picture above (this is kind of like having a McDonalds next to a Burger King) and neither store was particularly crowded at about 3 PM on a Saturday afternoon. There are actually two branches of Bannai in Gotanda, the other branch is called the Gotanda Eki Mae branch. "Eki Mae" = in front of the train station. The Eki Mae branch is larger but is also closed on Sundays. Overall I definitely like Bannai. On this trip I also purchased (1260 yen) a take home box with soup base, pork pieces, menma and noodles (the noodles come from the store's stock, the rest is prepackaged). I got three more meals out of this (OK actually two). Few large ramen chains have this, Tenkaippin does too actually now that I think about it. The original store on which Bannai's ramen is based is located in Fukushima Prefecture and apparently is so popular that they have tour buses that go to it.
Nishi Gotanda branch map+address (西五反田店)
Diddlefinger Map (English labels)