It depends. Does your twin actually care and want to do this with you or is she/he just humoring you? Partnering up can be dangerous if one is not as passionate and/or dedicated as the other. Twin channels can be fun but make sure you're both on the same page with where you want the channel to go. If your twin is neutral or not really into it then I caution starting it WITH them. You can still start it yourself and feature them from time to time but if you start with a person then when the person leaves or becomes less active then the audience will likely lash back and accuse you of being a bad sibling/co-host. But if you just do a "featuring my twin" thing then those episodes the viewers can look forward to as special treats instead of making it the norm. With that approach if your twin's passion dwindles then it isn't a big deal, it just means that your "featuring" videos become less frequent.
I must say I am on the outside looking in and have no idea what kinda chemistry you and your twin have and thus having a joint owned channel may be fine. But because I don't know for sure I ask you err on the side of caution. Sit down and talk to your twin, make sure they're serious about this, potentially, life changing decision. Hopefully I'm not coming off as too cynical, just a bit paranoid is all!
Anyways, good luck!
