Since you don't need it for travelling, just get the 5726. Very useful complication and it's thinner. 5726 is my go to daily watch.
The 5990 looks and feels sportier because of the heft and the chronograph function. If you want sportier, 5990 but the there's at least 10k usd price difference. Only you can answer if it's worth the premium especially since you don't use travel time.
I love how PP made an ear shaped travel time function to maintain the look of the Naut. They invested money with the new tooling!
