I debated what to get - the tractor is an L175 - 15 pto hp, 48" wide tractor.
what needs worked is about 18 acres of horse pasture - they don't eat everything so the weeds need kept after.
Talking to many folks the concensus was 48" - for power, for weight (i have no loader). Some said a 60" would be fine..
I found a used 48" king kutter, fairly heavy duty compared to what rural king sells now..no clue how old it is.
I have ZERO issues with it - weight is fine, spin up (gear driven pto) is fine, up hills, etc - no problem.
I've not hit what I call 'heavy stuff' - solid 4' tall weeds, woody plants, etc. I've run over saplings (up to 3/4 inch or so), vines, weeds 18" ish tall and it never misses a beat, no bogging even up hill.
Issues: - 18 acres is huge! My thought was I can mow faster so 4 foot or 5 is no difference...NOT TRUE - sure, i can cut fine in 2nd gear but the ride is WAY too rough out in the pasture to go that fast.
So maybe I shoulda gone 5'...I know a guy with a 5' and was gonna borrow it to see ... may still do that. Plan to get a bigger tractor later this year or next spring when the car is paid off , so this 4' may only be a one year deal.
Weight of the hog isn't an issue - it's got that rear wheel so the only time the tractor has to pick it up is for SOME transport - just shtu off pto and drive with it down..no probs.
And to add, i'm cutting about as low as it will go - 6" maybe. the only bogging I had was running over the remnants of a roundbale that was wet.