I'm only running a 2.5 Terflex coil lift (and it's my first). I am hapy with it so far but not much experience to compare to others just yet. Plus, mine is only 2.5 not the 3-4 he is looking for. Depends on his budget and how he plans to wheel it..,.
If you are looking for a nice lift kit that won't break the bank, Rubicon Express suspension is a good choice. Rubicon Express is a basic kit that comes with everything you need to lift your rig. It allows you to keep proper roll geometry since it uses an axle-mounted rear track bar bracket.