Bench is absolutely horrible, never been good at it, haven't done it in 3 weeks. I've squatted 535, pulled 620. At 45 I'm looking to ramp up and set some new PRs this year.
Great work! You're doing stuff better at 45 than I did at 30, and under it seems...... And you're natty too, IIRC? I was gassed for my lifts, but oddly none of them happened on the heaviest cycle I ever did. All were done with 600-950 total combined AAS.
Like I mentioned, flat bench is my nemesis as well.

I hate it, but I grow from it.
I've done incline dbell benches with 125's for sets of 10-12, but would only get 8-10 on flat with 120's???

That's not normal! Actually, I've even done dbell shoulder presses with the 120's for 10. Makes no sense compared to doing flat bench. I must be really effective at keeping my shoulder involvement during flats to a minimum or sumthin?
Good luck with hitting the new PRs! I'm just gettin into it again, but heavy stuff under 6-8 reps will no longer be a thing for me going forward.