Well, the Smart Wool ones are not flimsy, at least in my book. I have been wearing them under a pair of slightly larger full fingered gloves for rides below 45 degrees or so, down to 32 so far. I tend to be hard on gloves, so if they were to rip, it would definitely happen to me. I wouldn't want to wear them alone, though, as I think they would be too slippery on the bar. I have had several (one a year) pair of wool liners from EMS and they ripped every year; hence the spending of more $ at the end of last winter, to avoid this.