Owned both myself. 4200 has better coatings on the lense(possible better glass as well though not sure) but it is superior in transmission, clarity and brightness. Everything else is the same as the 3200. If you can get a good deal on the 4200 then go for it but paying close to to double (that is the retail case up here) I'd personally save me pennies and buy the 3200 or move up. Short eye relief, weight and styling hold the 4200 back from being a great scope for the investment IMHO.