i've heard that a strip is easier in terms of how fast you get it done, but individual ones tend to look more natural if placed correctly (but i guess more time-consuming). the strip would probably be easier for most people, especially beginners... but i haven't tried it yet (i hope that info helped a bit, though)
the good thing about idividual lashes is people prefer to use those when they want something that looks a bit more 'natural'