4" backspacing will work fine, but depending on where you go four wheeling, more backspacing may be better. Do you four wheel in sand and rocks, or in dirt/mud? I live in the mountains and it gets muddy around here a lot of the time. I've had 4" and 4.5" backspacing wheels before, and now I've got a set of wheels that have 5.2" backspacing. I've noticed my Jeep stays noticeably cleaner with the tires tucked back under the fenders a little better. And no tire rub at all with my 35" tires. Just something to consider. The money you save on wheels may be offset by money spent at the carwash.
2017 Jeep Wrangler Rubicon Recon; 35s - no lift, Warn 9.5 XP-S, ARB Twin Air, SPOD
2017 Jeep Grand Cherokee Trailhawk (wife's Jeep)
2016 Ram Laramie 3500 Megacab 4x4; 6.7 CTD, Aisen, AEV Prospector conversion; 37s, 4.10s, Warn 16.5K