Depends on your needs
Have had LR3 HSE for nearly two years and and 38,000 miles and love it. Have taken it to difficult places, and it has outperformed so many older Land Rovers. I think the Sport vs LR3 is really a utility issue, but can also be affected by how tall you are. The LR3 has so much more room, and if you need to haul stuff around, or need 7 passengers, go with the LR3. If you aren't too tall, and want more nimbleness, go with the Sport. I love the sport, but it just isn't big enough for my activities. But the Sport is just as good offroad as the LR3, so that really isn't the issue. If you camp, the LR3 can carry it all. I surf, so I always have gear, surf boards, etc., and can carry quite a load. In fact, it rides even better with a little extra weight. Gives the air suspension a little more resistance.
I have the running boards, since I am always putting surf boards on the top. Have to be careful offroad, but they are easily removable with a few bolts if you need the extra clearance.
You can't go wrong with either, but if room is a factor, go for the LR3.