You can do whatever your wallet allows you to do, but jj951 gave you some good advice. I rode k's of miles on a no-name Japanese steel 10spd, then a Raleigh, then an aluminum Trek in the 80's before going with a custom in the 90's. Also just bought a stock cf bike. Point being that, for me, I had to put in a certain number of miles before my mental focus was for certain on me rather than on the bike. For instance, when I got my Trek, I got it from what is now one of the top Trek dealers in the US and the owner fitted me personally. The guy was totally qualified and did a good job, but I had no real idea of what a good fit was and just had to trust him. Fast forward thousands of more miles and I had a pretty damn good idea of what I liked, didn't like, how I rode, where I rode, features and components that would add value vs. those that would add only cost before I paid for a full professional fitting from the best shop around. Then I shopped around and, because I am 6'1, 200+lbs with a fairly long torso, ended up going the custom route.

Although you didn't provide any measurements that would indicate you need a custom, unless your proportions for your size are out of the norm, you probably could fit a ton of stock bikes. Again, I highly recommend custom - just that some need it, some just want it - non issue. I think that it would be helpful if you were at the kind of place I described - where you know your likes, dislikes, capabilities and the component market before you sunk a lot of hard earned cash into a custom. I know others who were not at this point and, although I don't think any regret going custom, several now know that they didn't get the kind of value they believe they could now and could have gone off the rack for hundreds less with no issues.

Good luck.