The klasse twins will give great protection and if your looking for more gloss you can add additional layers of KHGS or top with a nuba topper. Adding another sealant on top of the Klasse may be overkill since I get 6-8 solid months of protection from the Klasse alone.
I would also personally avoid mixing different "classes" of products because I wouldn't want to jeopardize bonding and longevity.