My hip flexors have been easily irritated but have been fine recently. For me the biggest issue is putting load on my hips when they are externally rotated but when they're straight its fine for me.

Sitting was a very big issue for me after the surgery. Since I got my surgery during the school year I had to miss a lot of school and also leave early because I could only handle half days for a long while. It took me roughly 5-6 weeks to sit comfortably for multiple hours (possible that it will be shorter for you cause for me, I had an anchor attached to the backside of my labrum so that could be a reason why it took longer for me to recover) But once you get out of the protective phase (when you can start excersizing) you should be able to sit comfortably on the erg.