I just started using e-cigs within the last two months and I must say my first experience was similar to yours. I got a disposable e-cig from the corner store and I don't know if it was too old or what but I took one pull and got a mouth full of terrible tasting numbness. I didn't even think about trying again until a few weeks later when I saw an Ego starter kit for sale at a local smoke shop on sale and went from there.
The it seems like the two most important things are having something that can be reliable all day and having a flavor or a few flavors that you won't get tired of and that are also fulfilling. Make sure you have two
batteries so if one dies use can use the other while charging. I like the ego kits because the batteries last a really long time. As far as flavors go I would recommend alien visions. They have a tobacco flavor called Bobas Bounty that is FANTASTIC and I would also recommend the root beer and strawberry they have. Another "e-
juice" vendor that people seem to like is Deejstuff. I have a bottle of his peppermint flavor that has really cool(cold feeling) but not overpowering flavor if you like the menthol thing