With LATCH, it's about the same. Does their car have LATCH? Simple, nothing to it. If they have only seatbelts, then pop open the red and gray lockoff in the middle of the base, put the seatbelt in the belt path (same as the SR), pull the shoulderbelt so the lapbelt gets super snug, and then clamp the lap and shoulder sections of the belt in the lockoff. Voila, that's it. No need to even pull the belt all the way out to lock it, if they have switchable retractors, and it should get totally tight just pushing it down with your hand, no need to get your knee in the base to tighten it or anything. Harness is about the same, but they have extra loops in the lap straps AND the shoulderstraps (SR only has them on the shoulderstraps).