GUYS: How should I talk to my husband about his sexual performance?

I know this can be a sensitive area for guys, so I’m looking for your advice. We really need to do something to draw out the duration of our “play time”. Right now, we do the start-stop thing to keep him from finishing too quickly. My problem is that there isn’t much start time. It’s constantly stop stop stop, and it’s driving me crazy. I’m not even sure what our options would be to improve this situation, but first I need to figure out how to break it to him that what we’re currently doing just isn’t doing it for me. Sex shouldn’t be a hassle or frustration, and right now it is. What’s the best way to approach this conversation without hurting or offending?

Basically, I thought this would be a great question to bring to Fluther so that I can get some real feedback on how men prefer this topic be approached.