Which product would be the best "holy grail" foundation that comes to mind?

I used to only use cushions, but as I get older, I feel like I really need to try foundation as well.

I had similar concerns and have tried various products, ranging from Lancôme Teint Idole and Shiseido Revital Essence to NARS Light Reflecting and Espoir. Each has its own attractive strengths, so the choice may vary depending on your personal skin type and desired coverage and moisture level. However, speaking from my experience, Shiseido Revital Essence is great for its moisturizing properties and natural glow. I liked Lancôme Teint Idole for special occasions because it offers good coverage and lasts a long time. NARS Light Reflecting is excellent for creating a light and radiant complexion.