I have tried a couple of other biners and this is by far my favorite. I can't believe how light they are.
Some other lightweight biners I have tried were too small... tough to work with especially with gloves on. I am much happier with these. If you ice-climb only the smaller size could be a slight drawback so you probably wouldn't want a full rack of 'em.
It is smaller than a standard biner but seems to be big enough to do the job... great for racking gear, great on quickdraws and general use.
If you are trying to drop some weight from your rack I highly recommend these!
I picked up about a dozen of these for racking gear. They are nice little biners - lightweight and sturdy.
The drawback is if you have meaty hands or do any climbing in winter then these can be difficult to handle because of their small overall size and small gate opening. And if I try to use them for rope clipping they will work but I'm not able to open the gate when my middle finger is inside the biner... so the technique I use to clip them is limited. If you have large hands or wear gloves I definitely don't recommend them... My second did a fair amount of cursing when cleaning gear with these biners.
I found other lightweight biners to be a better value. Their slightly larger size is just enough to overcome the issues I have with the FS Mini.
Overall these biners are good and I am glad I have them but will only be using them for racking gear or for the bolt side of quick draws.