Samsung Galaxy Grand runs on a 1.2GHz dual-core processor, 1GB of RAM and on the back there is a capable 8-megapixel camera. The camera features backside illumination sensor (BIS) for better shots in low-light conditions, and it is capable of recording 1080p video. The Grand also has a front-facing, 2-megapixel camera for video calling. It all runs on Android 4.1.2 Jelly Bean, which should mean that performance is smooth lag-free with Project Butter.
Recognised XDA developer, pawitp has released an early CyanogenMod 12 build featuring Android 5.0 Lollipop for the 1st generation Galaxy Grand Duos (GT-I9082 and GT-I9082L), which is still on older Android version 4.2.2. Follow the guide to install CM 12 on your device.