Blowjob

So my last boyfriend was bigger than my current and I could go all the way down and he'd come in decent time, every time. like less than 10.

My current, I've only given head before sex mostly and only once or twice I tried to just give head and not have sex and he didn't cum and ? I gag more with him? I understand guys are different but it was a little blow on my self esteem with blowjobs. I don't really like it when guys try to throat fuck or hold my head. Half of me thinks its hot but I gag and it irritates me a bit. which he also likes it when I gag a bit but that was too much for me. He is uncircumcised and I hear that's different too. tips? extras? I want to make him cum from head. and I dont mind doing it longer either but it just didnt seem like he was enjoying that much. sometimes it does but others it doesnt.