If you're going to go insert, go Thunderbird, and get the yellow flame model (not the blue torch flame). Blue flame torches will all eventually stop working correctly. They're just too finicky... and they go through fuel fast. I've owned both brands. The Thunderbird is ingenious. It uses the same flints, and the cam is cleverly designed to be the fuel release, so you just flip the lid and it activates the fuel (just like pressing the button down on a Bic-style butane lighter), then you spin the flint wheel just like a normal Zippo insert and wham, fire. Close the lid and it closes the cam.
That said, I tried the insert and eventually went back to the old lighter fluid insert. Why? Because the advantages of butane did not outweigh the disadvantages of butane (compared to lighter fluid).
ADVANTAGES:
smells better
does not evaporate
DISADVANTAGES:
much less windproof
no flame in cold weather
I don't mind the smell of lighter fluid. In fact, it's kinda grown on me, and I like it now. As for the evaporation thing, I have a routine of refilling my Zippo every two days, so it never goes dry on me. And I really, really appreciate the windproof nature of lighter fluid inserts and the reliable flame in the cold. So... I started using the lighter fluid insert again and have never looked back.