Wow, it's kinda weird. I look at that poll and just can't vote. I see 510/ego/mod/whatever listed, and it's my view that when we say 510, we mean 510 atomizer. Honestly, the battery is not the e-cig, the atomizer is. Sure they give different batteries different names, but it all boils down to what atomizer it uses. I started off with a 306, knew I had to get something "better" for me, and moved to a 510. I've been really happy with it. I've tried the KR8's and 901's and found them lacking. That is of course only my opinion, as others love them and detest the 510.
I've seen a lot of threads with people recommending the ego, and I would also recommend it if the new user didn't mind the size. Some people want small cigarette like e-cigs, start vaping, realize they love it but hate the battery life, and then quit caring about size. Sure it costs them more in the long run, but it also leaves them with a spare, or something to loan to a friend that may be interested. You can get a 510 starter kit from cignot for 35 bucks, use it a while, decide to upgrade, and you're really not out much. The "510" is also versatile. I have 306 atty's that I can slap on and turn that bad boy into a "306" in an instant. I can get LR atomizers or cartomizers if I want. I currently DO use a mod. I had a spade and recently upgraded to a Prodigy v3 and gave the spade to my mom. I still consider myself a 510 user, because thats the atomizer I have. I do not consider myself a "prodigy v3" user.
The simple point here is that the 510 is an e-cig that has been around for quite a while and helped a LOT of people stay off the analogs and care about vaping enough to even consider a bigger battery, whether it be an ego/riva/mod/whatever, therefore it is what a LOT of people recommend. If it worked for us when we were in their shoes, we assume/hope it will work for them. Most of us that have been here a while didn't have the luxury of an ego/riva/or the vast amounts of mods that are around today. I tell them that a 510 is a great atomizer but they will eventually forget about wanting something small and move up to something better because they will get disgusted with battery life.
FWIW, I really never see anybody recommending auto batts. They have been discouraged against for as long as I can remember. Now please, can we stop pretending like batteries are anything other than a means to power our "e-cig".
It's all about the atomizer baby.