That Naxos (ex-Koch) was my least favorite Feldman recording, and I sold it (after buying as a Berkshire cutout). The only other Feldman recording I ever sold was "For Philip Guston" by the California Ear Unit (on Bridge), which I liked in places, but was just too long for me...
Disclosure: No more than personal taste, but I don't find the string quartet timbre optimal for Feldman; apart from solo piano (a favorite), I seem to prefer hearing, say, mallet instruments, perc., piano, winds, etc. mixed in. I haven't heard (or had a big ambition to hear) the monster String Quartet #2 for that reason. The one-disc Koch quartet disc dragged, and even grated on me a bit.
On the other hand, YMMV and Naxos price encourages experimentation.
I listened to "Neither" again last night, and now more strongly recommend it. I prefer it to, say, "For Samuel Beckett", which I also listened to last night. Sound quality was better than I recalled, though a wee bit murky.