Personally I haven't bought anything but Mobile 1 for at least 15 years...
I've always used Mobil1 oil and filters in everything. It might not be the best out there, but it's definitely not the worst. It's readily available. And the price isn't horrible, especially since they run sales on it every couple of months at the auto parts stores. Yes oil/filter quality is important, but I think even more so is actually performing the maintenance at regular intervals.