No you will have more Caliper clearance with the ET20 because the wheel is spaced OUT an additional 10mm. I'm not sure what kind of brakes you are running, but most VW brakes are set up for a +38et. The caliper clearance usually comes into play with the shape of the barrel of the wheel. Once again though with a 16 inch wheel there shouldn't be an issue with that since most 4x100 VWs have small brakes to fit inside a 14 inch wheel.
You should ask these questions in the Technical Section/Wheel Fitment Forum. If YOU don't know if YOU can make them fit, don't buy them. It isn't the sellers job to figure out if they will fit on YOUR car.:thumbup:
Since you obviously have NO idea what you're talking about, I made a special teaching diagram just for you, buddy:
Observe that a higher numerical offset (such as "20mm is higher than 10mm") means that a wheel will be spaced further inwards compared to a lower numerical offset, assuming the wheel width does not change. So an 8-inch wide wheel with 10mm offset will sit further in from the fender and closer to the suspension/middle of the car compared to an 8-inch wide wheel with 20mm offset.
Therefore, if you don't change the shape/curvature/thickness/etc of the spokes, and want to gain that 10mm of offset (to go from +10mm to +20mm offset), you have to machine away 10mm of material from the hub..... so, the spokes move closer to the hub and to the brake calipers. LESS brake caliper clearance.
Take a look around - you'll see the many of the really concave-faced wheels are either really wide or have a lower numerical offset. If you use +50 offset, like on a lot of Porsche wheels, you end up with very flat or even convex-faced wheels (bulging out in the middle).
Hopefully that wasn't too much text for your 20-second Generation-X attention span.
I didn't ask about wheel fitment. I asked if the seller knew anything more about his wheels than the very basics, for the purposes of non-factory brake clearance. I should've known better than to ask a technical question on a teeny-bopper forum, my mistake.