The two years of my life where I have had to work 60+ I was absolutely miserable, ended up quitting the job. That number of hours means you're not doing anything but work, getting to work, getting home from work, putting food in your food hole, watching How I Met Your Mother, doing laundry, and going to sleep. Never again and yes I regret both of those years, I should have quit and moved to a different employer much earlier.
I've been in my industry for 14 and those two years feel emotionally like half of my working career. There's an enormous difference in quality of life between 40 and 60 because those last 20 hours are starting to come out of vitally important activities like dating and seeing family and building relationships with people outside of work. I think I have mild PTSD from those years. I wish I were kidding.
In your OP you mentioned you could probably get away with being closer to 40, can I ask why you're going 60, is it because you are hourly or booking billable hours? Is your job more stable if you are seen to be working more?