I would normally have no input for this thread - however, after having spinal fusion surgery January, 2023 I had to drop down in weight for this year's hunting season as I'm simply not back in full shape (strength-wise) yet. So I bought a black hunter to be able to shoot low poundage cheaply this season. At my draw, it's 41#. I was able to take a 5 point (pictured in another thread I posted) and I got a complete pass through. I hit it in the 3rd to last rib on the entrance side and it exited right behind the off side shoulder (quartering away). Broadhead was an 3-blade VPA - YES a 3 blade (that's because I can get that head so sharp, that I'm almost afraid to get near it).
My son just killed his first trad deer - his bow is a 45# vintage Browning Folding Hunter. He pulls it to 27", so ~ 42#. He also took a similar angled shot on his buck and same result - complete pass through with the ACE Standard.
My other kill this season was a small 8 point with a 49@28 Browning Nomad Stalker (~ 45/46# at my draw). I hit that deer slightly forward of the crease and it went through both shoulder blades up to the fletching. I was astonished with the devastating penetration. That head was a Magnus Classic (1 1/2" 2-blade).
Our low poundage bows have been very effective for us this season. HOWEVER, I plan to be back to my 60lb bows next season. I also believe you need to shoot the max poundage you can accurately handle. For me, having always shot heavier bows (from 55 to 70#), I really struggle with a clean release with the light weight bows... string just doesn't want to leave my fingers. I like the feel of the heavy bow's release - it's crisp and snappy. I like the slighter margin for error that a heavy bow affords me - mainly because of the same speeds but a much heavier arrow so far greater kinetic energy. But again - my results show you that you can indeed get very efficient kills with the lighter bows.