There is another option to sitting or standing at work – Focal calls it the 'Third Posture'. Focal's products allow you to work upright in a natural, neutral posture.

Mobis I Leaning Seat * DEMO SALE *
Mobis, the adjustable height, lean-into seat and perfect partner for any standing desk.
Locus Leaning Seat with Anti-Fatigue Mat * DEMO SALE *
Locus Seat doesn't have you sit or stand. It helps you discover the perfect in-between position.