Just my 2cents ….
I’m 6’3” and a fairly regular size 😛
I have recently just gone from a L Soul to and XL Solaris.
With both bikes designed to run shortish stems I found the Soul to be a little cramped. I have always liked a long TT and the XL Solaris certainly has that!
I have my Solaris set up with an inline post, 70mm stem and 762 V1 flat bars. The same set up albeit with a layback post on my Soul felt nimble and chuckable but even with a Thomson post I was getting close to needing a larger frame.
Only have a short pootle on the Solaris but immediately its a better fit and feels more comfortable.
Have sold my Soul ( 😆 ) now so guess that makes me a Solaris man 😉
The buying of a Solaris though is all bol’s fault 😆