I have used various amp wiring kits from Fosgate's Competition line of products in the past and still have some of it - got it on the very cheap from ebay though. Good count of tinned copper strands and flexible enough.
This time around I bought Knu's Krystal RCA interconnects, some Kolossus power wire, and some Karma speaker wire (and booties for me wire...). The RCA's seem real nice - I would say they are very good in build quality and by guessing they shouldn't give me issues sound-wise. The Kolossus and Karma are effing sweet. Very high count of tinned copper strands and very flexible - will use these items for now on as long. I have seen bad references about their distribution blocks from several people now and Hillbilly makes another so I will keep a wide berth with them.
Use Darvex to buy quite a bit of terminals and various other items from - usually real fast at shipping the order out, reasonable pricing and haven't had anything bad with them happen so another place worthy of recommending.