One word of warning about the cozy R&D department of a product org: you may suffer from the boiling frog syndrome. Little attrition and long-time continuity means everybody stays in their seat and there a few true career opportunities beyond seniority promotions (dev - senior dev etc). After 5-10 years you find yourself quickly at the end of your promotion trajectory and realize that much younger/cheaper folks have the same role as you. This puts you at a disadvantage in salary negotiations and increases the risk of being let go. Project-driven orgs can be brutal environments, but there is always a possibility to climb up the ladder due to high churn.