Using /31 for router links

In the past I've always used /30's for PTP connection subnets out of old habit (i.e. Ethernet that won't take unnumbered) but now I'm considering switching to /31's in order to stretch my IPv4 space further. Has anyone else does this? Good? Bad? Based on the bit of testing I've done this shouldn't be a problem since it's only between routers. ~Seth