What are the pros and cons of being co-supervised?
Pros:


If one supervisor gets hit by a bus, you still have a second supervisor who is familiar with your work and can thus give constructive comments on it, hopefully appreciate it and in particular evaluate it. Often, your supervisor is the only person at your university who is actually capable of fully understanding and properly judging your thesis and defense.
If one supervisor turns bad or turns out to be bad and for example gives bad advice, makes ridiculous demands or even expects you to do questionable things, you can still turn to the other supervisor for advice or to have a serious word with the bad supervisor. If the relationship to the bad advisor goes totally awry, you may have the option to drop them and be supervised by the other supervisor alone.


It depends:


You may be expected to do more or less work. For example, if you are doing an interdisciplinary work and have one supervisor from each discipline, the supervisors may only understand and value the work you do in their respective half and thus think that you did not do enough. On the other hand, they may also overestimate the work in the respective other half and thus be more easily satisfied.
You can benefit from the experience of both supervisors and learn something from one advisor that you cannot learn from the other.


Cons:


You may be affected by disputes between the supervisors. For example the first supervisor may tell you to do something in a certain way and then the second supervisor blames you for it.
If aspects of your work require input from both advisors, you may need to wait not only for one supervisor to have time for you but for two. This is in particular difficult, if you need to talk about something with both your supervisors at the same time.


Some of the above obviously depends on the details of the relationships between your supervisors and the reason for the co-supervision. Thus, you can only judge yourself, if these points apply to your case and how important they are for you.