Any toilet, manual or electric, that's working anywhere near factory spec can lift bowl contents at least 4'...Vented loops often have to be that high when the boat is at rest to keep 'em at least 6-8" above waterline at maximum heel. 6' linear feet is actually closer than the tank is on many boats.

If you read the specs for the Elegance, you'll see that it's designed to lift at least 10' and move waste 100 linear feet, so it shouldn't need another flush cycle just to move a flush a paltry 4-6', even uphill.

As for my thoughts about the VacuFlush...once upon a time it was the only game in town if you wanted a toilet designed to use pressurized fresh water and needed less than 1-3 gallons/flush...but those days ended in the early 90s. Now every toilet mfr offers at least one model designed to use pressurized fresh water, and very few toilets today need more than about 2 quarts of flush water...which is also about the same amount that the VacuFlush actually needs, despite SeaLand's claim that it can use "as little as" 1 pint of flush water....that's VERY carefully worded. If only urine is flushed...no water added to the bowl first, no TP either...then yes, you CAN get away with that little, at least for a few flushes. But if you do much of that, unless you want odor, at least once a day you need to run at least half a bowl of clean water through it to rinse out the system. It's also advisable to add at least half a bowl of water ahead of solids or any TP (iow, every time a female uses the toilet)...that's a quart or more. It's also essential to leave the pedal down for at least 7-10 seconds after the bowl is empty to rinse out the pump and duckbills--to prevent a buildup in the pump or bits of waste or TP from becoming stuck in a duckbill, creating one of those pesky air leaks that causes the pump to cycle for no reason...at least another quart. And if you don't want permeated hoses, it's a very good idea--last thing before the boat will sit (or at least once a week if you're living aboard)--to fill the bowl to the rim with clean water and flush it through to thoroughly rinse out the vacuum tank, hoses and pump...'cuz suction splatters waste all over 'em and the flush water flow isn't sufficient to completely fill the hoses. So, averaged out over a week, the VacuFlush actually NEEDS about the same amount of flush water as most other toilets that use pressurized flush water: about 2 quarts. If you you're using much less than that, you're asking for problems.

Btw...I had V/Flush toilets on my last two boats and was also a dealer for nearly 10 years...so I'm INTIMATELY acquainted with 'em...what keeps 'em working trouble-free and what doesn't. Today's macerating electric toilets offer everything the V/Flush does--and MORE--for a fraction of the price and require almost -0- maintenance...a rebuild every 5 years or so...that's it.

As for whether you have to move the Elegance to service it....once every 5 years or so is a small inconvenience to avoid components scattered all over the bilges that need new duckbills and other service every year or two.

And finally, my thoughts on manual vs. electric. Manual toilets require a lot of maintenance...frequent lubrication and rebuilding at least every couple of years if you live aboard. Otoh, macerating electric toilets--at least the better quality ones--need -0- maintenance. And I have to grin when I hear sailors say, "but if there's a power failure, I wouldn't be able to flush it!" If you have a power failure so catastrophic that you don't even have 10 amps to flush a toilet, whether you can would be the LEAST of your worries...'cuz you won't have nav equipment, communication equipment, lights or anything else you actually NEED to get safely to the nearest port...but you WILL still have a bucket!