Okay, given the fact the primary intended use for the bike is going to be for commuting in L.A./Orange County CA, I have to ask where will you be 'parking' your bike? If it's leaning against a wall or some place that you can keep an eye on and there are no other bikes around it, then get whatever you feel like. However, if you have to lock up at a community bike rack or other place where other people will be locking up as well, then I'd shy away from carbon forks.



As far as what size frame will fit you- you claim to be purchasing from the LBS, they are more qualified to assist you in that area, since they will be able to eyeball it.