Rule one is fit, particularly on a touring bike where you spend all day in the saddle. If you get the wrong size, even if you make it work, you are going to probably end up paying more money down the road since when you ultimately switch frames, not everything will be recoverable, like the stem, tape, cables, and so forth. It's not a deal if it isn't what you need. You will also waste time you could spend learning something about what a really counts on a real touring bike that fits. You may develop preferences that come back to the fact you own the wrong frame.