As with other reviews, the performance difference between stock springs and sumo is clear. The facility isn't that bad. There are various tips and tricks videos and suggestions. Choose the one you think suits you. The biggest challenge for me was the space. The RV has rear hydraulic stabilizers and I'm not a small person so it took a bit of fiddling. Make sure you use the Sprinter's jack points and jacks and you'll be fine. The front springs fit very well.