Taking the shoe out the box it looks totally different to previous models - in a good way and just like (or even better) than in the pictures I had seen. The first change is the hole in the heel to make it easier to pull the shoes on and off. At first I didn't see much point in this but now I find myself looking for it on other shoes! This hole is also on the Gorunride4.
The upper has changed as has the sole which is 3mm thicker. This has added a little extra weight - size 7 ladies GOrun3 weighs 187g the Gorun is 210g. As with the Gorun3 the heel drop is 4mm or you can take out the insole giving a zero drop and a more minimal ride. I have not run without the insoles as the shoes would then be too big (I already have a slightly bigger size than normal shoes).
They come with 2 sets of laces - I have not tried the red ones but will probably swap them over when these start to look grubby!
I was never keen on the tongue on the Gorun3 - it was too thin/floppy. The new tongue is much better - more padded so more comfortable.
I received the shoes a few days before the London marathon and since I had the limited edition London edition felt it would be rude not to wear them! I wore them for a few short test runs then for the marathon with no blisters or bashed toe nails!
As with all skechers shoes I found them very comfortable out the box. They are very light which makes me feel fast even if that is not the case! The previous editions were softer, a more slipper like feel; these are a bit more firm and feel like they have a little more support (not over pronation type support). The Gorun ride4 has changed in a similar way (see review http://helenrunsultras.blogspot.co.uk/2015/02/skechers-gorun-ride-4-review.html )
Gorun has been my Speedwork and race shoe (up to marathon distance and the occasional short ultra) but now there is less difference in weight between the Gorun and Gorun ride (which is my everyday training shoe) I will probably wear the Gorun4 for more of my training runs as I prefer a lighter shoe and the extra weight means it is more suitable for every day use.