I am using both, N9 is main for daily use - calls, sms but Jolla for net browsing and keeping an eye on development, features, improvements, apps ...
I bought N9 as used phone and after some time I found out that skype integration was messing up with contacts, also wi-fi is still not stable, some minor problems.
I believe there are better pieces out there.
Also I like size of N9 and found out that it is easier to type on N9 then on Jolla, hmmm ?
I am using uniboot, did flash so for future I think will stick with N9 untill possible.
now I hope will get lynx and gt5 to get work, no success till now.
still it is 60% for N9 and 40% for Jolla in way of use.