If you really value the GMT features and that is what really matters to you...independently of the aesthetics, or any other concept, I would go for the RLX.
Panerai is selling basically 2 different GMTs movement. ETA based models (like the 88) and Manifattura Mov (like 233 f.e.)
One based on the VALJOUX 7750...well known, reliable...but IMHO not good if you use GMT function frequently. In this mov the 24HRS is the one moving in 1hr jumps and also is not related with the date, what IMHO is not very useful. In case of traveling to another time zone, you should set this 24hr as your HOME TIME....to know if in the other time zone is day or night...and use the normal hands (Hour and minutes) as LOCAL TIME. This makes you reset the hole watch each time you need to travel (if a big time zone difference)
In the maniffatura mov. its done the opposite. The GMT hand could be always used as HOME TIME ( also is linked to the AM/PM indicator as its not a 24HR hand) and then you can "jump" the normal HOUR HAND in 1HR movements ( this hand is linked to the date). That is the normal way and also how the RLX works.
The only BAD thing of this Panerai movement is that its not featuring FAST DATE adjustment.
On the other hand...you have a huge Power reserve (8 days or 10), not having that in the RLX. Also you can hide the GMT hand in these Panerai, when you are not traveling, so you have a clean dial, and an awesome domed crystal!
If the fast date change is not a problem for you...I would go for a PAM233 or PAM270. Or even the PAM275...!