If you're going to do a lot of cutting you will use way more oxygen than acetylene. An 80 cf bottle is far too small to have them drain off at about the same rate with a 75 acet. I use a B acetylene (40cf) and an 80 oxygen which is the largest my gas supplier sells for an owner bottle. My O/A is 95% cutting use. The plasma cutter doesn't travel well.
If you work in a shop setting it could be even more; in a past life I was in a company that did on-site work and we went through lots of oxygen. Turns out on Monday mornings the crews would throw a small O/A rig in the back of the 1-tons and pass the cutting handle through the passenger window and hit off it going down the road. Works wonders for taking the sting out of hangovers. The owners were WTF are we using so much? Finally just swapped out the 60cf for 80's. Some things you just can't fight.
Not saying you'll have that problem....
Harris dual-stage O/A
Lincoln AC/DC buzzbox
Miller 3035 spoolgun
Thermal Arc 185
Thermadyne Cutmaster 52
Angle grinders, vicegrips, the usual suspects
Two hands, tired body, not enough time...