M8,
I haven't tried the yellow carlack, but I have tried & continue to use the Klasse twins & the new nano twins...
IMO the nano twins (clean + seal) are easier to use than the Klasse items and also provide a fantastic clear, gloss cover with a noticeable slicker feel than the klasse twins...
It's an improvement, that to me means I may no longer purchase the klasse twins when my bottles run dry... Nano clean on its own is a very good product which always leaves a nice glossy finish. Nano seal just provides added "zest", more gloss & protection I guess...
When I feel the paint after a few days with my fingertips, its a slicker feel than the Klasse twins (which I still really like btw) and doesn't look like its going to disappear as some other waxes & sealants I've used in the past...
So go ahead and try the nano Seal over the carlack - can only get better I reckon.
:goodjob