Check these four things before switching
Check whether your banks can connect, whether historical transactions can be imported, how data is handled and whether the features you need are included in the price.
Then try the app with your own numbers. A good finance app should make your next choice clearer, not simply show more charts.
What does Flusii cost?
You can try Flusii free for 30 days. Premium is then DKK 29 per month unless you cancel. Always check the current price in the app before confirming.