Likewise agree, no problem. I run 5 ft head pressure with 20+ ft horizontal run.
Remember, the Tunze has a speed/power adjustment that can be turned up. The default setting is 'medium' speed. It can be turned up even higher if you want.
You can look at my build thread, but I have my Tunze osmolator adapted with a pushloc fitting and hooked to RO tubing. The RO tubing has a 5 foot vertical run from the pump, then runs along the periphery of the fish room to my sump for a total horizontal run of ~20+ ft. The osmolator is running on the 'medium' speed setting (haven't needed to open it to adjust the speed dial). No issues whatsoever. Not even running it at full speed so you will not have any issues