I agree with Phil 100%. Partnerships are precious, even the bad ones (because they will teach you how to recognize a good one in the future). Give it a try for a month and see.
I think it's very beneficial when you're getting started to take lessons together with your partner and also private lessons alone with your own teacher. That way you've got time when you and your partner work together to bring together each of your own dancing, and another personal time where you can work with someone who isn't your partner on issues that arise. You might tell your private teacher "every time we try to do a double reverse spin I get all confused and do this other thing" and your teacher can help you to really understand everything that you have to do so that you can respond in the clearest way possible to your amateur partner when you dance together. Or your personal teacher might want to spend time developing your posture and frame so that you can take that back to your amateur partnership and present your partner with something more connected to work with.
You'll find that if you take a combination of group classes, personal privates (no partner), and coaching sessions with your partner, plus going dancing with other people, you will learn the most about dancing and about your own dancing. For instance, if you find you keep having the same problems no matter who you dance with, then for sure it's something you are doing wrong and not the fault of your partner. Then, you can get extra help on that issue from your personal private teacher.
After a while you'll know when group classes don't work for you any more, or when you need to focus on just dancing with your competitive partner, and so on.