It really depends what you want. Do you want to just chuck crazy outrageous clouds OR would you mind sacrificing some clouds while STILL blowing large clouds BUT getting AMAZING flavor to boot? Personally I would go with the Derringer due to the flavor it provides. I own ALL of the RDAs you listed and I personally think the Little Boy stinks, the Dark Horse is GREAT for clouds but it has a really tiny juice well and the flavor just isnt good enough FOR ME, it still produces decent flavor cause its an RDA but the flavor is really muted. The Derringer cranks out perfectly acceptable clouds AND the flavor is simply amazing. I usually don't get excited over new RDAs because I know what I like in a RDA and the RDAs that I really love I own doubles or triples off but the Derringer got me really excited. It can hold a lot of cotton as well and has a pretty nice sized juice well for being one of if not the shortest RDAs on the market (shorter then a penny lol) so it can hold a decent amount of liquid. The Derringer IMHO looks stunning and the size or lack of size is one aspect I really like about it, I put it on a Praxis and its literally like the size of a cig. I put the Derringer into my rotation of daily RDAs and that is really saying something because as I said earlier I have what I like and use it and although I buy a lot of drippers I rarely actually use any more then a few times but the Derringer is different. I personally have been enjoying it with a parallel 24gauge .2 ohm coil on a Praxis. The flavor is really, really good. I am first and foremost always going for flavor and this little guy does not disappoint however it still puts out great clouds its just not on the level of like a Mutation, Doge or some of the other "cloud chaseing" attys which is fine by me because the flavor more then makes up for it.
I think you should go with the Derringer my friend. Its really easy to build to so you don't need to be intimiated if you haven't done this before and once you put "your build" in there I can assure you that you will be very happy with the flavor.
Now, if you want clouds, go with the Dark Horse point blank period. Out of the drippers you have listed it provides the most clouds however be prepared for what I consider a muted flavor, small drip well and an extremely airy draw. YMMV though and you may like the Dark Horse and hate the Derringer which is really why at the end of the day you gotta get out there and try these devices for yourself and you will come to know what you LOVE in a dripper. Like myself, I know EXACTLY what I need in a dripper and I know what drippers will do it for me but when I started into RDAs I had no idea what I wanted and had to try about ten RDAs and use them for about a year before I really nailed down what I like. Now I have 6 drippers I use for flavor and three I use for cranking out the clouds and the others just sit in those rubber atty stands on my dresser lol.
As for the gauge of wire, I really think you should do a lot of research to answer your own question but I will give you a basic run down. The lower the number the thicker the wire so 24 gauge is really thick and 34 gauge is really thin, also the lower gauges have LOWER resistances per inch so they will provide a lower resistance then a higher gauge wire provided both builds used the same wraps. I personally do not use anything lower then 24 gauge and I would suggest any new builder start with 28 gauge. Its a nice middle of the road wire and you can do some good builds with it. Check out steamengine it will help you with your builds. Please build higher then 1 ohm during the first stages of your journey into building. Once you have done tons, and I mean TONS of reading you can start SAFELY and CONFIDENTLY building sub ohm coils (if you want, you dont ever have to I am just saying you SHOULD NOT at the start of your building career.) Make sure you get an ohm meter so you can check the resistance of your builds. It isnt near as simple as this gauge will provide more vaper because A LOT of other factors go into that. I would go with a 1.2 ohm 28 gauge build to start with. As I said steamengine will tell you how many wraps and such to do. Please do this safely my friend. Research your battery limits and how that relates to the builds you use, always use an ohm meter NO EXCEPTIONS, do NOT go to low, stay above 1ohm for the first builds you use and so forth.
Have fun man, drippers provide the BEST flavor IMO.
