Boone. I love his story and he's a SNIPER !

Vanilla-wise, almost definitely Cass, I just can't help but like that snarky bitch with a heart of gold. I like how she has more commentary than some of the other companions, though I have recently learned Arcade has quite a bit of that as well. At first I really didn't care for Arcade, I thought he was, as he puts it, "Boring". So I never actually traveled with him too much before, but now I rather enjoy his dry quips and commentary.

Mod-wise, that's a bit tougher; I'd would say Russell because of his involved quest but Russell himself kind of creeps me out a little with his kill lust. He can also get a bit grating with how much he bitches about the NCR. Now, I don't have to have all my companions be cheery and optimistic but at least Boone is just a bit of a buzz kill, Russell tends gets a little obnoxious about it (IMO). I still think it's a great mod and outside those couple of gripes I do rather like him. I also enjoyed Willow but I hate that fact you can't fire her. It just seems unnecessary to always have her in your party from the moment you meet, whether or not you can just have her wait somewhere indefinitely.

Gonna six this bit*h. Her lines are what drew me in. Her sneak stat is handy too, for snipers.

I like Raul,just the way he talks to you ,it makes much more fun to play with him and Niner,what I do not like about him is that he is too over powered,you get Niner outside Goodsprings so really early in the game ,he just took out all powder gangers in the prision,so he had to wate for me,and I could have some fun

I choose Willow and Cass. Right now, I'm trying out that Vanessa mod that was released recently. I have to smuggle/scavenge/buy out a lot of whiskey just to satisfy her.

however many people i can dress up badassily (if that's even a word)

My favorite is Ulysses. Especially when I'm doing a role play kinda play through with just me and him. His voice actor did a real good job in my opinion. It sets the mood no matter where you go. I've been meaning to try and get a screen shot with both my courier and ulysses sitting at a campfire on a starry night as Ulysses talks about his views.

I personally take Boone as he is incredibly OP for the time period you can get him in.

Definitely ED-E, the little guy's like my own personal R2-D2!

@Snowboarder I laughed a bit.

I always like Sergeant RL-3. A robot with a personalty and makes you laugh every time you try to get its attention while being able to take out enemies. Getting his ammunition for his guns was never easy but always worth the extra fire power he brought with it. Getting shot in the back randomly always made me think I was getting attacked but when I turned to see him it made me laugh rather then being angry.

My favorite companion is Jericho from fallout3. I think this guys crude humor and pissed off attitude is appropriate for the game itself. I love when i'm getting wrecked with him, he always says some funny shit, plus his "f#^@k you" dialog with other npc's never gets old

I really enjoyed Boone for his story and hidden questline and he was a beast with his rifle to the point where he would just steal all my kills, then I got Niner who also had a really good story and quests to follow, I really liked how he was a companion but his quest also went along with the games story to the point where it seemed like it shouldn't have been a mod but in the full game.

For vanilla companions my favorite is hands down Veronica. Interesting backstory and she destroys pretty much anything in her path with her original power fist.

However, my favorite modded companion is definitely Niner. He's a funny, drugged up freelance who doesn't take himself, or life in general too seriously. His sense of humor is a nice comical relief from the harshness of the wasteland.

This.
http://www.nexusmods.com/newvegas/mods/37388/?

Seriously, who doesn't want to have a deathclaw as a pet? Better yet, grow it from egg to a 8-foot killing machine. You even get to name it. Come on.

All the vanilla companions are pretty well made to be honest, even though I usually just bring along Boone and Rex, I still like them pretty equally.

Other great picks:
Niner is hilarious, but overpowered for my early-mid game taste. Russell is a pretty immersive companion too, especially if you love bounty hunting as much as I do.
Ulysses is definitely one of the most interesting characters in the game, and you can get him as a companion thanks to mods. The only real downside to this is that you miss a epic boss fight, which this game really doesn't have enough to be honest. Luckily there's the save-system time machine

I would say Cass. Cass alone is just an amazing companion and I don't really have a single problem with her. He quests are good and she has personality better than... Well most if not all the companions in new vegas are great but I would say cass is the best out of the rest. Also the only mod I would say that can help her is the new vegas character overhaul. Other than that she is perfect.

For vanilla,my favorite would have to be Rex just because I love having a friendly dog at my side,and he reminds me of dogmeat.I MISS YOU DOGMEAT-rip died during my fallout 3 playthrough he was too young.

My favorite followers is Boone, never used any downloaded followers cause I didn't really see a point. I like Boone cause of his quest line and his usefulness with a rifle.

Fawkes from Fallout 3. That super mutant and his Gatling laser are best, never get bored wandering dc ruins with him. Heres my list:
Fallout 3:
1:Fawkes
2:Dogmeat
3:Charon
4:Jericho
5:Star Paladin Cross
6:Sergeant RL-3
7:Butch DeLoria
8:Clover

New Vegas:
1:ED-E
2:Craig Boone
3:Veronica
4:Lily
5:Rex
6:Arcade
7:Cassidy
8:Raul

Boone's great and all, but I've always had a soft spot for Veronica. There is a strength to her character that I appreciate, while at the same time a playfulness that enjoy having as a companion. During my first time through FNV, I made it a quest to find that illusive dress she was always reminding me about.

Not a companion I know, but you've got to love Toaster from Old World Blues. Can someone please enlighten me if anyone has/or considered making him/it a companion?