Promotion?

I've been considering something a lot recently that should be an obvious decision. I'll explain, but first a bit of build up.
I work as an inbound telemarketer. I actually moderately like my job. Furthermore, I'm really good at it. Good enough that I spend about 1/3 to 1/2 my time supervising, even though I've only worked there about 4 months and I'm not a supervisor. I make good money doing this. I was recently offered (told that the job's mine if I want it) a promotion to trainer. The problem is that I don't know if I want it. Points to consider:
I make $9/hour plus bonus on the phones. My bonus amounts to at least $3/hour more every week. I would make $12/hour as a trainer. This means I make more on the phones. Being on the phones requires more work though.
My hours currently are 2:30-midnight Saturday-Tuesday and 2:30-6:30 Wednesdays. I don't dislike these hours, but they make it difficult to hang out with certain friends that don't stay up until 2 or 3. As a trainer my hours would be noon-8:30. These hours are still fairly good. In fact, they're probably better.
Furthermore, I have serious job security as the trainer because The company will have invested time and money in me. Plus, I will then dictate how many breaks I get each day and when. I'll have to follow rules, but it'll be different ones. My appearance will matter, although it doesn't right now. That brings me to my next point.
I really want to dye my hair red. Not a natural red, but a cool red. I haven't been able to dye my hair in a long time and I've wanted to. If I were to be the trainer I couldn't have red hair.
If I were to accept this job, I would, in a way, feel as though I'm saying "this is what I'm going to do with my life." While I don't have a problem with other people doing it, I don't want to spend my life as a trainer at a telemarketing company. I know I shouldn't look at it like this, but with all my jobs I've ever had, I've noticed that moving up means settling in.
I obviously don't know whether I want the job or not. I think I may turn in my application and r�sum� and then dye my hair and decide later. I don't even know how long I have to decide. I'll check tomorrow when I'm at work. Eh. That's all for now.