Sharpening gang mowers is a PITA,to be honest,but it is required much less than sharpening on a rotary.The Jacobsen's I use are basically self sharpening.I have to get off and adjust bedknife clearance about once every 4 hrs,unlessim going over some rough ground,then its more often.I have 2 sets of 7 gang mowers,the better set has 10 blade reels,and delivers an ultra fine cut for fairways,it is set at 3/4" most of the year.This set gets backlapped,about a 20 minute job per unit,once a yr,unless I have a bad operator,then twice.The other set has 6 blade reels,and they only get backlapped every 3 or 4 yrs,or as needed,you can see when one isnt cutting good,then if i cant adjust it out,ill put a new bedknife on it and backlap it.I almost think maintaining them is easier than rotarty moews,once you know how to set them up properly.You never ever have to scrape,you can let them build up with grass if you want,they cant plug unless you run them thru 12" of grass,then anything will plug.The pull tupe i use are extremely efficient,i can pull a set 15 ft cut easily with my 32hp ford tractor.I have pulled them with my 24 hp Onan Steiner too,in a pinch when the tractor was being used for other things.One thing you cant do with reels is cut tall weeds and let the grass get out of control,you have to maintain the area,no going 3 weeks then cutting a ft of grass.