Champagne this is not.
I have yet to find an alternative to a good Champagne; other fizzes are often perfectly adequate as alternatives, but are still defined by their relationship to Champagne.
This sekt is very different to Champagne, yet equally enjoyable; more fruit forward, it is more of an elegant table wine with bubbles.
Henkell Trocken NV floral with yellow stone fruit, citrus and a fine mousse. Substantial, crisp and refreshing with a mineral finish. Good underpinnings and no rough edges.
Will improve with age.
Drink as an aperitif; a great match with fish and chips or curries.