With the numbers you have (height, inseam, shoulder, torso, etc. etc) Canyon's PPS is your best bet to prescribe your CF. I'd need an accurate seat height to do better. Don't be put off by the vacillation between small and medium. Prolly half the population can fit on a small, medum, AND a large. And I'm am certain that if I had the numbers I like to work with I'd still offer up two different sizes. The proof is in the numbers:
The Pad Y range (this is how much the pads can go up or down) on the small is 582-669 and on the medium is 605-692. The overlap of 605-669 is huge! 65mm. That's a ton.
The Pad X range (this is how much the pads will shorten or lengthen the cockpit) is 447-472 and the medium is 467-492. The overlap there is 467-472 that too is pretty healthy - of course is even more than that realistically because both those bikes come with an 80mm stem yet they make a 70 and 90mm stem if one needed it.
I'm an advocate for being fit BEFORE you buy a bike but if that can't happen than I'm adamant about getting fit once it arrives. Canyon has a 30 day return so if you really do need a small you can get it but chances are you'll fit well on that medium.
Thank you for the comments about my fit based on the minimal parameters that you provided.
I am back from from a work trip and took some additional numbers:
1. Center of BB to the front of of pads is 570 mm (to the back of my pads where my elbow/back of forearm sit is approx 500 mm). Could also pull the pads and aero bar in about 10-20 mm without a fit problem to reduce this pad x.
2. Center of the BB to the top of my pads is 620 mm
3. Saddle (ISM PN 1.1) height at the front part of saddle is 1000 mm
4. Saddle height at the rear part of saddle is 1030 mm
5. Nose of saddle is just about even with the front of the BB (I generally dont sit with my hip bones at the front tip of the saddle but prefer to sit a little bit further back with my groin hanging just off the front end of the saddle).
6. Current Crank: 175 but want to go down to 165 on Canyon
Hope this provides more insight into my current fit that i have...
Any recs between small and medium are much appreciated. Thanks!