Better seats for G class WDB 463

Dear forum visitors, I have tested a used G55 model year 2003 (WDB 463) today. I am interested in the purchase and this would be my first car of this class. I noticed – and I am aware that this was already criticized by other drivers – the execution of the seats in this G class. I did not find a good side support and also the seat, or the leg rest appears to me quite short (although I am not particularly big with 1.78 cm). I am not very comfortable. is that with the last model revision also the seats have been improved, however for me, such a young G55K from financial guilds is not possible. My question is therefore whether someone has experience with an exchange of seats. Are the new seats available for example and can be installed at a G of 2003 or is there possibly a specialist company that offers a retrofit? What is the experience of the G-drivers with the seats? If one gets used to the quite spartan seating comfort or tiresome I would be happy to hear about experiences and much more about exchange and/or improvement tips. Warm greetings, D. PS: What I also found interesting on the test drive is that from speed 170 km/h the sheet metal of the bonnet really got into vibration. You can also call it “flatten”, although the hood was correctly closed. Is this also normal?