Posted: 23/10/2015 at 00:03
The correct answer is based on exactly what difference you're looking for.
If it's a question of comfort, then basically you need to bite the bullet and get your gait analysed.
If it's a question of getting better at running, that's harder to answer on a forum.
As an example, I started in a pair of clearance Asics I bought from JJB because I liked the price, and although they felt nice on my feet in the shop, they put me off running for years after I got excruciating shin splints.
I thought it was just a matter of my age, until I tried to take up running again many years later, got my gait analysed, and was told Nike Vomero would be my best bet. I have never had issues with shin splints from the moment I first tried Vomero 1 on.
However, they are a squishy sod of a shoe, and aren't exactly built with speed in mind. Through my running my weight came down quite a bit, and suddenly I wondered if I needed quite as much cushioning. A runner friend recommended Nike Pegasus, I tried a pair on, bought them, and within a fortnight I'd got PBs in about six different distances.
So it's not exactly an exact science. Take expert advice in the real world, and maybe bite the bullet on a full-price shoe one time only. Once you've identified a shoe that's perfect for you that doesn't leave you in pain after runs, then you can start bargain-hunting when it's time to get additional pairs or upgrade when they're nearing the end of their life.