The Pro version is a little lighter but more importantly, it has an improved inside layout with better features for securing your bike.
Another notable difference is the disk brake rotor protection. The original bag has some protection while the Pro version is much more substantial.
Here you can see how a mountain bike and road bike will fit into the original bag.
Mountain Bike Packed
Here you can see mountain bike its rear wheel of the bike fit into the travel bag pro. When compared to the original, there are more straps, padding, and protection to keep the bike safe and secure. Included with the pro version is the frame pad, which wraps around the top and bottom tubes.
When it comes to wheels, disc brake rotors and cassettes, there is more protection. There is a thicker guar protecting the rotor and two braces to help protect the entire wheel.
Road Bike Packed
As you know road bikes are much smaller than mountain bikes, so you will have more room for your bike or more room to pack a larger bike.
In addition to the frame pad EVOC provides a road bike adapter to help keep everything snug. the road bike adapter fits around the front forks.
The same wheel protection will help protect your cassette or disc brakes if your road bike has them.