I'll just say "Welcome to the world of X-Metals" now aus, because I know once you buy one it's really hard not to buy another!
Given the fact that smaller frames do indeed suit you, metals may actually be right up your alley! They're thinner and smaller than nearly all O-Matter frames and I can't see them being a problem for you! I would definitely start with a Juliet! Not too big, not too small and if you decide that X-Metals aren't for you, they're easy to pass on for a sale or trade! Not to mention they're great for customizing! Change t-shox, ear stems and lenses and it's like you have on a whole new pair of Oakleys!!
Obviously the downside to owning metals is that fact that the nose bridge loosens over time and needs to be sent in to Oakley for repairs (with the exception of the X-Squared, which you can tighten yourself) Having said that tho, being careful when taking them on and off (trying not to over extend the ear stems) will make them last a much longer time!
The pros are plenty, but to me, the most important one is that you have a pair of sunnies that can take an absolute beating and won't break!! As for causing headaches, I have no problem at all with any of mine. I have heard of people complaining tho so I guess it's up to the individual.
NOTE: Be careful when purchasing X-Metals tho, there are a lot of people out there charging WAY too much for them. Definitely shop around and ask lots and lots of questions before jumping in!!
Good luck with your new addiction (I know it will be once you buy a pair) and if I can help in any way whatsoever, feel free to send me a PM!!
