I think I was lucky or we just ride the same. Our very first tandem ride was a metric century on a borrowed tandem. We figured if we could do that then we'd be compatible enought to buy are own, which we did but a few years later. Once we got our own it took us 4-5 months to get everything dialed in so we were actuallly comforatble. Some of this was bike fit but also technique . Give it some time and be nice to each other during this stressfull period.