AFAIK, the primary benefit of an air-to-liquid IC is it allows for shorter charge air plumbing and less boost pressure loss. Also, for track purposes under the right circumstances you can reduce inlet temps to below ambient levels when using ice water coolant. MB's tend to have very little room to mount an IC, so a air-to-liquid setup might actually be the best solution, especially if you don't want to alter the external sheetmetal. BUT, they're typically much more expensive than air-to-air versions.