All the SYR releases are challenging to listen to. This is more challenging than some, and less than others; whether you approach the problem of learning to swim by diving into a fast flowing or slow flowing river is moot; but with SYR you will be dampened... I suppose my feeling is that you might as well get properly drowned as only a litte; so i'd start with the second, more dense part "slapkammers" if, howver, you only wish to test the waters, then Annagramma is your bag. (should you feel like taking up aqua-aerobics whilst wearing concrete overshoes, then "goodbye 20th century" is the one)
I don't see that it is possible not to buy all of the SYR ouvres if you have one; they are just too fascinating. I feel slightly cynical that sonic youth could have packaged all of the 1st 3 eps into a single album with some coherence, but marketed them this way for kookyness and art (oh and perhaps money too!). if they had done so, there could be a just accusation that this ep is all the filler and lesser material. that might explain why this one is separate from slapkammers. these tracks would reduce slapkammers somewhat. the next question, of course, is why release it at all? well, out of the shadow of the other works, it's pretty good; and context can't prevent art. the whole ep approach obviates the need for albums and "B-sides" releases, so this is probably "valid" to that extent.