Performance for applications and games is night & day compared to an old laptop I was using. I'd expect anything modern would be a lot faster than something back in 2012. Battery life is excellent for my use case. The 99.9Wh battery goes a long way as I can get a whole days worth of battery life in a single charge. My one gripe with this laptop isn't fan noise or temperature. If you are looking at the GS series you should expect high temps and loud fans during high load or gaming sessions. You can only cool so much in something this thin. My one gripe is quality of the body. For this price this should've been a unibody design like the Razer 15. MSI decided to use a cheap feeling plastic trim for the front. Not only is it cheap, its as though it was just an afterthought. When you feel around the laptop your nails get caught on it, very unrefined. I've owned this laptop for barely over a month and all I have done was walk it up and down the stairs and already the edges of the trim is either cracking or already broken off. So now I'm expecting that front trim will completely break off once I start packing this thing and carrying it around. Again, at this price point, its unacceptable. If I could do this again. I'd most likely consider the Razer 15 since it doesn't have that cheap feel like how the GS66 does.