There are differences.
For the smell, I feel like the particular Dirt one I tried might have a slight advantage but it's not very important since preferences are so subjective and both brands offer different scrubs with different scents. I got Ola Vanilla Ginger scrub and Dirt was a Purify+Glow but had no name to the flavour like there is now on the Glymm website. I don't know if that's a recent change or not so I can't even really tell if they sell the same flavour I got as a sample...
For the "feel", I found the Dirt one kind of greasier than the Ola one (from memory), though it was definitely a nice moisturizing scrub. Still, I prefer Ola.
For the overall experience, there is a major advantage to the Ola scrub because of my eczema that is still acting up on my hand. Salt on it stings a lot and made for a pretty crappy experience for me.
For the price, Dirt sells 12oz containers for 45$ and Ola sells 8oz containers for 24$.
Dirt = 3.75$ per oz
Ola = 3.00$ per oz
I am really loving this Ola scrub and I am considering a purchase of the full size product. I would for sure highly recommend that anyone who enjoys these types of dissolving scrubs try them out!!! I can't imagine a person could have a flat out negative experience with this product. It's pleasant to use, smells so great but not overpowering, it's just a nice experience.