There have been widely varying experiences, but I've had excellent service from this one:
http://www.amazon.com/True-Utility-FireStash-Keyring-Lighter/dp/B0045OW0N2
Mine is I think two and a half years old and I've filled it once, on Christmas day, the day I was given it.
Haven't touched it for months. I've just taken it out of my pack and it lit first flick.
No lighter that I have ever had - and I'm a semi-professional pyromaniac so I have a lot of lighters - has ever come close to this one for reliability and the longevity of a fuel fill.
Having said that it's my go-to emergency lighter so it doesn't get a lot of use, I usually use one of several cheap Chinese blue-flame things that I keep kicking around.
The link above was just the first one I found, there might be much cheaper sources of the same lighter but I'd buy it at that price if I had to buy another one.
Oh - if I haven't said so before, welcome to BCUK!