Have not selected a bile or stem yet , My riding experience is that I like larger for climbing (calmer front wheel and easier on the lower back , but the new geometry sitting upright WAAAAY better on the lower back ). I think the new bike designs are made to drop the seat and push the bike out doing down , but if you not dropping it much the bikes may feel small ?? Rode both the hd3 in large and xl and it was an easy choice for the XL but that specific bike was known to fit small. Tell the snow to melt in Tahoe !!!
I'm 5'8" with relatively short legs (30" inseam) but average wingspan and the M felt cramped but the L couldn't get the saddle low enough at full extension. Ended up going with the L but swapped the cranks for a set of 170mm (my long-time preference) and the dropper for a OneUp to maximize travel at my relatively low saddle height. Also needed to lower the bar height by swapping around headset spacers. It's SO NICE to finally have a bike with proper reach, even if it took some customization.
I’m curious as well. I need up selling my large Ripley and replacing it with a medium Ripmo. It took a year to notice, but the Ripley was too long and started causing me shoulder issues even with a 35mm stem and the saddle slammed forward. It descended great but the pedaling position was too stretched for me. The Ripmo is a little shorter and I still run it with 35mm stem and slammed saddle, but my shoulders are much happier.