Seems like it would take longer to put the sail up with a "push-up" sail. It comes down fine with the halyard set up. When I ordered my new main there was the option of a "push up" style but I didn't give it much thought. I can't see how it could make any difference in sailing performance. I have never used a push up main so I can't say for sure but it can't be significantly easier to deal with than a small lightweight halyard. Besides, if you have mast up (very secure) storage you can use the halyard to tie to the end of your boom to keep it up and keep the mainsheet blocks extended so it doesn't get kinked, etc.
p.s. new Glaser main (white) and spin (orange) should be here today!!