If you're gonna "build" up a spec bike, my biggest advice would be to know how to do it. In other words, be handy with tools, and know which ones to have and what they are used for. It's not too hard to assemble a bike, but if you don't know how to wrench, don't "learn" on your dream bike. Other than that it's great to spec it just like you want it, and it's even fun to scrounge for parts. I built one up earlier this Summer. K2 Mod 5.0 frame and fork with mostly DA/Sram/FSA drive train and other liteweight parts that I like, each chosen for it's function, reputation and weight. Parts were found through Ebay, Mail order/internet stores and even the good ol' LBS. Be ready to make changes though...just as you would any high performance bike. For instance, I didn't like this bike when I first finished it, it felt kinda dead. But I swapped out the seatpost and wheels and I'm much happier now, in fact it's the best of the 3 roadbikes I own. One last thing...I chose the K2 frame because I wanted a compact frame and it's Med geometry was exactly like my trusty old Bottecchia SLX vintage bike, upon which I've logged many K's. My point is, I had a baseline to work from. If you don't like your current ride, ie. fit and feel, it's probably better to try out prebuilt bikes and find one you that fits you. Another option would be to get a "fitting", to find your ideal size. There's a lot of data to take into consideration other than a box of parts. If you can conquer all these issues (and more) then by all means I highly reccommend a do it yourself. I did save money... $750-$1000, over the prebuilt, both on parts and labor and I enjoyed the process and feel a ton of pride when I'm rippin' down the road on MY machine. In closing you have one other option...most LBS will charge about $150 to assemble your pile o' parts, which ain't too bad considering it took me about a day to put mine together, of course I was savoring each step...I'm such a geek <g>