I prefer smaller, more frequent meals. I actually broke up my betta's feeding schedule into 3 meals a day in an effort to curtail his tailbiting and it seems to be working better than 2 meals a day. But that's also because there's almost always someone responsible home to do so- I know for many people that just wouldn't be possible due to real life schedules.
I look at it this way- we're always saying that bettas' stomachs are only the size of their eye. So, how could they get enough food in one feeding to last them a day that wouldn't make their stomachs uncomfortably full? It just makes sense, but that's just my opinion. I also, unlike most, don't fast for one day, unless his tummy looks too big and even then I'll usually give him some daphnia. Every betta is different.