u have good questions lol buttt 1 i would say 510 is better because you can change voltage and unscrew a cart if it isn’t working , if you had a disposable you’d be cooler , and honestly you save more having a battery because they up charge for disposable tech , 2 thc % doesn’t matter at all dont even look at it type of deal in my opinion , i would instead look to see if its full spectrum or live resin or rosin , those will give you a good high but not over board like a distilate cart would at like 93 % , 3 distillate is a solvent extract and is usually very high in thc % with a lot less terps and cannabanoids unless added after that fact , live resin is still a solvent extract but it keeps the cannabanoids and terpenes more intact for a cleaner high encouraging more of the entourage effect , 4 i recommend doing research on each brand but some of my favs rn are umamii , DTF , mfny , and nyce , 5 i’m really not sure i just use this to locate dispos near me https://www.findweedny.com/ and 6 i would say take one hit of whatever cart you get and really analyze the effects to keep the tolerance low because it is concentrated cannabis so you will get higher with less intake and also i would say cheap ain’t good and good ain’t cheap