The solus will not do heavy truck. The modis and solus will do up to 550 without heavy truck but in order to do the semi and 650 and up you will need the modis and heavy truck. All the mac scanner is, is a OTC Genisus. Not sure if they have heavy truck for the Genisus, but ive used them all being a Diagnostic rep for Snap-on and even though im not any more i still have to say the Snap-on scanners are better. With the new update 11.2 you can run cylinder contribtion on 6.0.
On another note if you are doing alot of big trucks you may want to look at the Pro LInk which you can talk to your Snap-on dealer about. Snap-on owns Pro link