The boat I am using for instruction frequently has a Quantum stack pack.
It has two lines on each side to adjust once the sail is up: one line to adjust the forward part of the pack and another to ease the lazy jacks. So much for doing everything for the cockpit.
When reefing the stack pack prevents me from seeing if the luff tack line is at the gooseneck and whether or not the leech line is taut.
The lazyjacks lines make raising the sail a PITA as you have to monitor the battens so that they do not get caught.
The seams have ripped on the stack pack.
The zipper has broken.
The line that is used on the zipper has failed.
The last 3 I attribute to UV damage which cannot be helped.
It is incredibility inconvenient.
BTW - covering the sail when at anchor is not a good idea. If I want to use my sail, I want it now. In addition there is little UV damage at night.
I have also used Doyle stack packs - did not like them either.
Another BTW - when was the last time you had a salesman recommend another company's product.
I like a balanced boat; the first sail to go up the main. It is also the last to come down.
The sail cover comes off the dock and goes back on at the dock. The main halyard goes on at the dock and comes off when back at the dock. That is prudent seamanship.