Oral sex and letting him cum inside your mouth

Hey girls, I often give my boyfriend blow jobs which I enjoy doing and he loves. He wants to come inside my mouth but I am not sure. I have heard that it tastes really bad and that some people with strong gag reflexes really dont like it. I also wouldnt know whether to spit or swallow. I dont really want to swallow but I feel awkward spitting it out and i wouldnt even know where you would spit it to lol. I just feel like it would kill the mood because I would gag or something and he would get offended.

Any advice? Does it really taste that bad?