The first thing to do before you take the Xterra offroad is to remove the stock step rails. They’re strong enough to stand on but as soon as a rock hits them they’ll bend. They’re worth nothing on the trail, so take them off before you hit the trail. Plus if you take them off early you can sell them in mint condition on eBay for $150-$200. The use that money to buy you some real rock sliders.
Which kind you get is totally your preference but I recommend the Shrockworks or Calmini, I got the Shrockworks because I like how the stick out a little farther from the sides for easier jacking with the Hi-Lift. A word of caution when jacking with the Hi-Lift on a slider, make sure the jack wont slip but also remember to open your door so that if the jack leans in it won’t dent the door.