InsaneDawe,

Top tube length is no more a critical data in geo charts anymore.
In this frame the effective TT will be shorter then on a progressive, older geometry bike because of the much steeper seat tube angle.

The size L frame have a 490mm ST length which is ridiculously long for your height, especially if you really want to build a down country bike with a usable dropped length and enjoy the downhills.

With size M you'll get 6cm longer front center and 50mm longer wheelbase then your basic hardtail have. This mean more stability.

This is a XC bike, not a hard core trail/ enduro bike, you don't need 500mm reach. 475 will feel also really long after the cannondale.

Hi steveP!

I never seen this bike irl, but rode multiple bike with modern geometry. Ok, mostly more trail /enduro oriented ones, but I following geometries and can decide about my frame size from the charts.

I'm 180cm +-1cm depends when they measure
With 200cm arm span .

I would go with the size M with short stem <50mm and wide bar.
But a stem and bar easy to change if it necessary

The bigger one have too long seat tube and you won't be able to use a dropper post longer than ~125mm and it'll be in the way on downhills.

This reach size will also fill LONG in the begining after your old-school frame.