Most of my games are on those types of discs, since the 16x Verbatims were recommended, but my burner at the time could only burn 8x discs, and wouldn't even read the 16x ones for some reason. A-ok.
should be fine, but you might want to search around for the best burning speed, iirc there was a difference between the 16x and 8x (like 4x vs 8x or something)
Nobody knows thé best settings, because there are none. All lot of different types of disc and speeds will work just fine.
For me, burning at 2.4x on TDK DVD+R for example is working nicely, never had a failed disc.