I would say 5-6 hours for an EPS install, Its actually really easy to install all the parts. The Wiring is the tough part because you either have to purchase an entire wiring harness or buy a used one and make an adapter harness like I did. Its hard to find people that work on atv's that are good with wiring like that. I do a ton of wiring repair, electrical diagnosis, and harness building at work, and have alot of know how on how automotive electrical works, I can go into a little more detail on the wiring if anyone is interested.
If I take the 30 amp EPS fuse out the EPS Malfunction light stays on and it steers like it did without EPS.
Mine- 2011 Sportsman X2 550 With EPS!!-Warn 2500lb Winch, Guru Brush Guard, RZR H13 bulb headlights, KC LED Yellow tint Driving Lights, Rigid light bar mounted in the pod, Autometer Phantom Oil Temperature, Coolant Temperature, and Voltmeter Gauges, Polaris Low Lock and Ride windshield, Acerbis Handguards, Symtec Heated Grips and Thumb warmer, 2+2 gallon Rotopax Fuel packs, STI HD Beadlock wheels and 27" GBC Spartacus Tires
Hers- 2012 Sportsman 550XP EPS Blue Fire LE 27" ITP Mudlites on ITP SS212 Wheels, LED headlights, Mile Marker 2500 lb winch, Polaris bodyguards