I started alternating, though over time I tried out singletapping, which eventually got me torn between both styles. It was pretty frustrating since I would trip up and miss really easy 1/2 notes.
The problem, I gathered, wasn't that I needed to be consistent with one style, but that I wasn't good enough at either. I had trouble alternating 210+ 1/2's for more than 8 notes and my singletapping was limited to my middle finger. Similarly, I could only start streams with my middle finger, and alternating stacks of 1/2's was confusing. So I
practiced alternating and tried singletapping with my index finger more often.
Nowadays I really just switch styles as I see fit mid-song, switching my singletapping finger sporadically or alternating.