I like that we have all our data stored centrally allowing us easy navigation across channels; being able to see what is available at each of our stores helps keep track if there are any shortages or stock issues with products going out quickly.
The only issue I can think of would be how hard it was when setting up new stores as you need several people assigned to set this up properly - but once done everything runs smoothly so not too much an issue! Centralising store information gives great insight into where your customers want their next purchase from ensuring you're meeting demand before they even know about it meaning fewer disappointed shoppers (and less likely refunds!).