I have been doing a lot of keycaps switching lately, and I found that my preference is to use the Filco keycap puller to pull a few caps off of each row first, and then use the Realforce keycap puller to pull the rest of the caps out. This seems to be the fastest, most efficient way to get all the keycaps off.
The Realforce keycap puller is not as thin as the Filco one, so it is harder to start. But after using the Filco one to get a few out, the Realforce keycap puller is very easy to position into grabbing a key and pull it off.