To add on to the stability conversation...I kinda echo what everyone has already said about the 177.
I'm not the fastest rider, but I do occasionally push the 30mph mark on my rides, mainly on downhills. On downhills I push until 35 mph or so before my confidence starts declining. I think it has a lot to do with my (lack of) skills and the crappy surfaces around here and not entirely the bike feeling unstable. I would probably push it a bit more if I were riding on nicer surfaces. It doesn't feel as solid as my gravel bike, but I'm not sure if that's a fair comparison. Not as solid, but definitely more comfortable and supple.
On the flats I never feel unsafe but I do struggle to maintain speed above 30mph or so. I think I could improve that with different gearing, better fitness and a different wheel/tire choice, but a more aero frame would likely help as well.
For serious racing with hard sprints you may be better off with a different frame in order to work just a bit less, but the 177 is pretty sweet as an all-rounder imo.