I have now failed on two attempts on used Tri Bikes. I bought a Cervelo P5 (58 size) that didn't fit. I recently acquired a 2017 Trek Speed Concept 9 (XL size). We bought the tallest riser and I still cannot get the fit that I need in the aero position. Prior the buying the Trek, I had narrowed choices down to several brands that come with a stack height of 585 to start on their 61's. This list included QR (PR 5 & PR4), Specialized and Cervelo P2/P3. I am leaning towards the QR as their HQ is 100 miles from my house. Also, with a new bike, I will be assured that I can make the fit work as long as I stay away from the super bikes. I am really not motivated to buy a new rim brake bike from Specialized or Cervelo and have them announce their "new disc brake tri bikes" a month or two after I buy a rim brake version. Appreciate any feedback from anyone that is riding a new QR or has a 61. Also, appreciate the potential feedback on fitter, etc. Learned a lot but I am with a very experienced fitter. Issue is that I am 55 and not very flexible. That adds to my challenge.