What is your opinion on pair app development?

I have been recently asked to develop a new API/Interface at work. But instead of me working on the complete feature solo, I have been asked to share the work load with another dev. This mandates me to get into regular calls with the other person, design review our choice, get into aggreement and brainstorm, conflict resolution in Pull requests and a lot more issues. I believe I could avoid all this struggle and become the solo owner of the interface and submit it.

What are the general pitfalls you have faced with pair app development at work?