Those naked resistors are the latest and greatest for audio, from Vishay. They cost $16. ea retail for .1% (can get .01%) - not exactly cost effective, at least at this point. Vishay makes encapsulated resistors for NASA - used to cost $60 ea, wholesale ('90s). The blue Dales are good clean sounding resistors, I think a good choice. I've used IRC RC55 series for loading - .1% so I don't have to match em. They seem neutral (Mouser around $1.20 ea). Even if you decide to build a state of art contender, you might want something a little sweeter like tantalum, if you're using ICs. There's a lot of prejudice against ICs, but they're superior to anything else in this application, assuming you want neutral, not euphonic. Most designers don't know how to configure them for superior performance, and consequently some audiofools think they're only good for budget stuff.
I read the review on the thread below and some testimonials here. Gives me a felling of deja vu. I'll have to get off my ass and snag one of these before you raise the price. Don't know how you do it, you must have another source of income.