Anyone here ride a Boardman Pro 29er (the newest version, with 1X11 and 120mm fork)?

I’m looking into buying a 29er hardtail for XC and general riding, nothing too technical, and these seem great value. I know these used to come with a 100mm fork so would be interested how the extra travel affects the ride and geometry. Does the slightly slacker head angle make the bike less twitchy?

Also, what size should I be looking at if I’m just shy of 6ft? The geometry charts on the Halfords website put me bang in the middle of a Large frame.