Bottom line: The arcade-sourced games (I, II and LEO) are passable and worth purchasing if this set is ever discounted. The dynamics jump around too much in R-Type III. Delta and Final have been
needlessly remastered to be way too loud, and parts of it come close to
Death Magnetic levels of stupidity.
Casual listeners probably won't care, but you should know what you're getting and be conscious of what your money would be supporting. That's what a discussion like this is for.
A set like this is a big dilemma. Ideally, you want to support a company for taking the time to compile and release a collection of good old music like this, especially when some of it is brand new to CD. On the other hand, you don't want to support sloppy work, and 3 out of the 6 soundtracks represented by this set have been handled very sloppily.
I'm happy to have the product, but I'm very disappointed with more than half of it. If you absolutely must have one 2011 SHMUP box set, your money would be better spent on Gradius Ultimate Collection.