re lithium-disilicate reinforced glass ceramics better than porcelain? (Photo)

I had 8 upper and 6 lower porcelain veneers placed in 2007. Over the years I have dealt with debonding and fractures. Currently I am considering replacing the uppers first and than the lowers 6 months later with lithium-disilicate reinforced glass ceramics. Are these better than porcelain? I need to have a new night guard fitted so is doing them both at same time preferable or can I do uppers and get night guard while waiting to pursue lowers? Thank you