Gel to enhance oral sex for my girlfriend?

Hi, I really enjoy it when my girlfriend gives me a blow job, however I know that she doesn't like doing it that much, due to the taste. I always make sure I'm clean before we do it, but because it's become such an issue, sometimes it just feels like too much hassle and 'never the right time'. I was thinking about trying a flavoured lubricant or gel to help things along, in the hope that she won't be so hesitant when the mood/occasion strikes.

But I'm quite lost as to what product to get. Will any flavoured lubricant do, are they all safely edible? What should I look for in something to use as a oral sex enhancer? I've seen a couple of products marketed specifically for this purpose (eg. Good Head Gel and Sweeten'D Blow gel), but not quite sure whether I am limited to these.

Thanks for any guidance.