Relax, enjoy the ride and experience of purchasing a vehicle that I am sure that you will grow more excited about every day that you own it. There are other threads on this site that address a production change that was made in late May and affected VIN numbers higher than 516000. My Ridgeline was built just a few days and a few hundred units after the change was made. It has been absolutely flawless. No water leak, no wind noise. If you have the time to search and read all of the various posts about the water leak issue and the wind noise, I think that you will find that the water leak issue only affected a very small number of early production models and has long since been corrected. The wind noise issue has apparently affected a higher number of vehicles but, again, at least as far as I have been able to determine after following posts on this site, it appears to affect vehicles made prior to the production change. It sounds like there are two different sources of wind noise. Vehicles can have wind noise from the 'A" pillar, the rear roof trim panel, or none at all. I suggest that the vast majority of vehicles have none at all.
Now for the disclaimer. All of this is simply my personal opinion and is based on reading posts on this site by owners and my own experience as a Ridgeline owner. Although I suspect that Ridgelines with VIN numbers lower than 516000 have been sold and fixed by now, there could still be some on dealer’s lots. Check the VIN number of the vehicle that you are purchasing. Test drive it and listen for the wind noise. Unless it is a very early production model I seriously doubt that you could find one that still has the water leak issue on the dealer’s lot that has not been sealed and fixed by the dealer. Most importantly, you are buying a Honda. I never would consider purchasing a first year of production vehicle other than from Honda. If there are any problems with your vehicle you can have confidence that they will be taken care of. I really do believe that these two issues have been resolved at the factory. Current owners that still have the wind noise are suffering with having to diagnose and have the problems fixed. Thanks to this ROC site, owners can share their experiences - and their troubles - and the solutions. Very few other vehicles have anything even close to this ROC site for owners. Spend some time on this site reading posts and I am sure that you will read owners comments that express more excitement and enthusiasm for the Ridgeline than any other vehicle that they have ever owned. That absolutely is the case with me and at 54 I have owned quite a few vehicles. Read carefully and you will read the same thing from owners that have had either or both problems. Don't worry, be Happy!
The bottom line is - Go for it! Enjoy the ride. Welcome to the ROC!