Mate,
Go with gen if you can afford it and willing to spend that money! You'll avoid all the hassle and problems that might arise when going franken. To tell you a story:
I bought a Noob Daytona 116520 SA4130 with the white dial. The dial looked hideous compared to a gen dial. So I decided to go franken.
- So I bought a gen black dial (green lume) and matching gen hands because the lume of the noob hands didn't match and sent it to watchmaker for installation
- Then I thought the bezel looked really crappy and bought a gen bezel and sent it to watchmaker for installation.
- Then I had some problems with the movement and sent it to watchmaker for service.
- Then I thought the winding experience, screwing/unscrewing the crown wasn't smooth enough, so I bought gen tube and crown and sent it to watchmaker for installation.
- Now I'm unable to screw in the crown because some spring or threading or whatever broke and have to sent it to watchmaker for repair.
Go franken if you are going for a ride, can deal with the waiting game of sending the watch back and forth and eventual long term problems with the movement. Or just go gen with peace pf mind!