The high lift option raises the trailer about 3". I wish I had the option on my
Casita. It gives you more clearance at the hitch entering/leaving uneven sites and it puts the grey water exit higher to make draining into a grey water tote easier.
I sometimes scrape the bottom of the jack post entering a campsite. On one occasion I scraped a hole in the rubber J trap under the shower. Not a particular hassle to replace but slightly embarrassing when I exited the trailer and saw the stream flowing away from the trailer. That was an extremely tilted site. Never been on a site that bad since.
Most grey water totes are thick (tall?) enough that even laying flat it's an uphill trip from the end of the drain outlet into the tote. On longer stays (5-7 days) I sometimes want to do an intermediate drain of shower and dish water. I can drain into a dishpan and then transfer to the tote but it's another step. If I'm lucky, the site is slightly elevated and I can locate the tote lower off to the side. Or I use a pump I've modified for this application.