I tried Regenerist but have seen better results with the Neutrogena retinol products. You could also use ROC, the French line, with the same ingredient and an excellent rep in Europe. I use the serum during the day, no dry skin anywhere, and the night cream and eye cream at night.
The most important thing is to look at the active ingredient in the product and research it, make sure that it has a purpose, that it has proven itself to actually get results, and that these results are what you want. There are so many different ingredients out there: Q10, vit c, copper, hyaluronic acid, retinol, etc.
Browse More magazine and Vogue, etc and read up on all the latest in skin treatments. Then buy the product you can afford that has those successful age-fighting ingredients. The mags may focus on the Dior products that go for over $100 an ounce. We don't need to spend that much!
It wasn't clear to me what the active ingredient of Regenerist was, although I like their thick night cream for when my skin is acting up and needs suffocating with moisture, so I chose to focus on the wrinkle visibility reduction properties of retinol. I am pleased with the results.
Clare