I am good with paying 50% of hard back prices when I buy PDFs. I try and support the small and new publishers by purchasing PDFs. But some of the Big RPG companies are asking almost hard cover costs for some PDFs, thats harder to swallow.

Mutant Crawl Classics MC is even more Gamma World like and don't forget about reprints of Metamorphosis Alpha and worked with GW editions 1 and 2 with little effort.

Then you haven't tried a 1st edition AD&D/Gamma World mix. It was a blast back in the day and Expedition to the Barrier Peaks will be a blast to run my group through for sure.