Dish or general wheel design has nothing to do with offset. Offset is offset no matter who or how the wheel is made. It is a standard. Just like 2 meters is two meters regardless of where that meter is used or by whom. A drunken russian sailor or cambodian KFC manager.

The bottom line is, +42 is to aggressive for a regular WRX. If you go fender cutting and uber camber, it might work, but once again, you will have a headache.

You must understand, that when you ask a manufacturer what offset to run with a particular wheel made by that manufacturer, they will tell you what is the best thing you can run from their product line-up. Not best overall.

And, also, who recommened that for you? I highly doubt that Works japan would actually do that. Thats why they have agents. And, coming from experience in the industry, those agents do not always know what they are talking about.

 

They will rub the rear fenders (not sure about the front). When you run more + offset you run the chance of rubbing the struts and when you run less you will rub the fenders. Here is a link that explains how offset works https://www.i-club.com/forums/wheel-tire-59/official-tech-thread-tire-rack-55297/ (scroll down to the 9th post). What tires are you going with?

 

Someone needs to contact these vendors trying to recommend such low offsets and ask them to recommend the proper offsets.