I fitted one to my Mini Ripper and it fitted very nicely at first. I later changed my mind and decided to put the original seat and post combi back in and you would not believe the hassle I had trying to get that poxy alloy post out. The more I twisted and pulled the worse it seemed to get and after alot of swearing it finally came out
Luckily, it didn't damage my frame but you should have seen the alloy seat post. It must have hooked up on a tiny burr or swarf which left deep gouges in the soft, cr@ppy alloy it was made from. It was totally sh@gged and there was no way I would use it again so I threw it straight in the bin
I learnt a big lesson that day and now I prefer to use a good quality chro-moly post like a 13/16" Pro Neck or something