I have a T Bird insert and it works fine. Had it for 3 years and no problems. Like others have mentioned the fuel reserviour is on the small size but no smaller than in a Nibo or many other gas lighters.
A drop of light oil on the fuel lever once in three years, and putting in a new flint when needed is all I've had to do to it other than bleed it and fill it. It can be interesting if you don't bleed it before you fill it but then my Oldboy will spit and sputter, snap and pop too if I forget to bleed it. Bleeding it is very important...more so than in some lighters which you can just bleed now and then. To my knowledge all gas lighters should be bleed before filling but do we always do it?
Pay attention to the gas shutoff lever. If it gets to sticking causing the size of the flame to change from one light to another, just drop a wee, small, little, tiny drop of light oil on it. Did I mention that you only need a very, very small drop of oil? Don't flood it. It needs far less than what you'd put on the hinge of your pocket knife.
Oh, almost forgot...since it's in a metal case the lighter isn't a big fan of the cold. In winter I keep mine in my shirt pocket so it stays warm and it works well. I dropped it in my coat pocket once or twice and it didn't want to give me more than a wee sparkle of a flame. Warmed it up in my shirt pocket under my coat and it was back to it's usual co-operative self.
Would I buy another? Yes. But not until this one takes a crap. I'm not buying much of anything since I had to go on SSD. It just plain sucks to be...never mind. You don't need to hear me whine.
It seems that some people just get bad lighters. I've been told that the warranty behind them is good. Since I haven't had to return mine I can't say that for sure.
I had a Nibo that had a bad fuel control valve and it blew up in my hand. Stay away from Nibos. I do have one that works but I haven't forgot what the first one did to me. It was all over before I had a chance to get very excited about it and I wasn't harmed...just a toasty hand.