Canon PowerShot G9 X, a good choice as an upgrade?

I have a Canon Powershot 310 HS but in a video I saw it said that if you have the 300 HS there's no need to upgrade. However I think there surely must be a noticeable difference between a mid range camera released in 2011 compared to what's supposed to be Canon's best small camera from 2015? I'm considering other options, like the G7 X, Sony's smaller cameras and the Nikon 1. However the camera I buy must be small as I travel a lot! So is it worth the upgrade or maybe you could recommend another camera?

The G9x should have great quality in a very compact unit. However, I think its zoom range would often feel inadequate. I'd spring for the G7x.

Yes the G cameras are really good choice

Use this tool to get an idea on what to expect: http://www.dpreview.com/...f=mainmenu

Here's a comparison of sensors: http://www.digicamdb.com/compare/canon_powershot-elph-310-hs-vs-canon_powershot-g9-x/

Here's a side-by-side comparison of features: http://www.dpreview.com/...=canon_g9x

There's no possible way for the G9X, with it's 1" sensor, NOT to have much better image quality than the 310HS with a super-small 1/2.3" sensor.
The pixels are more than 2x larger which means lower noise and an increase in dynamic range.
The 20MP vs 12MP will show more details and allow for larger prints or heavy cropping.
The G9X can shoot RAW allowing you to recover details in the shadows/highlights that is simply impossible to do with JPEGs. With RAW, white balance doesn't matter. You can always adjust white balance in post because the data for the color and brightness are saved as separate values as opposed as a single value in all JPEGs to save space. JPEGs are 8-bit files that have 256 (2^8) shades from pure white to pure black. The G9X shoots 12-bit RAW files which have 4,096 (2^12) shades.

The lens on the G9X is only a 3x zoom. The longer the zoom range the lower the image quality. 3x is very mild in comparison to some of the bridge cameras with 30x, 60x zooms.

The LCD on the G9X has more than twice the resolution making it far easier to evaluate images.

Many people just consider image quality, but ignore the amount of control that the cameras have over the image-making process. The G9x has a full manual, and a shutter speed range of 30 seconds to 1/2000th. This allows for night photos and even astrophotography. The 310HS doesn't have manual settings, and has a shorter 15 seconds - to 1/2000th range, which for most people using this type of camera is not an issue.

Because of the larger 1" sensor on the G9X, the lens is comprised of a longer focal length which produces a shallower depth of field allowing for blurrier backgrounds. While it's not going to produce blurry backgrounds like an APS-C or 35mm DSLR, it's better than what a camera with a 1/2.3" sensor can do.

The video capabilities of the GX9 are far better than the 310HS too.

Battery life on both suck, so have a few spares if you do video.

What if it was the same camera, from the old parts that never got assembled, put together inside a new body some few years later and labeled as something else?

Point is if your existing camera still works, why replace it?