https://wccftech.com/initial-reviews-of-magic-keyboard-for-ipad-pro-show-its-limitations/

Apple's Magic Keyboard for iPad Pro has shipped early to a few customers, and their initial impressions show that the product has a few limitations that might make you re-consider your pre-order. Despite having a cantilever mechanism, the screen's tilt range is severely limited. The overall weight of the keyboard is also more than the iPad Pro, and results in a little over 1kg total weight for the combination.

The Magic Keyboard weighs in around 600 grams, and an 11-inch iPad Pro (Wi-Fi) weighs 471 grams. If you consider the total weight for a cellular 12.9-inch iPad Pro and Magic Keyboard, it borders on MacBook Air weight territory.