First of all I have to comment on your thanks to Trelja and that you were looking for that kind of information, Why? Did that actually sound like good information to you?
I'll give you a quick rundown on why I would consider there to be value on my opinions about cable. I was a dealer in high end audio products, I like high end sound but also finding equipment that is a top performer at a price point. When I started I realized that if you tried to find out anything about wire and how much to spend you would get as many answers as people you asked. Even the people that have time and experience can be full of bull. I had some equipment lines that were the best values in audio, and others that cost a small fortune. I wanted to find out where the point that cables performance became a diminishing return because I assumed there would be one. I tried all kinds of relative value things like taking a BAT system with a $10k preamp, $18k amps, $6k cd, $22k speakers. Everything performed beyond it's price tag. The cables that are the best I've ever found going through about $400k worth of everything under the sun are the best value in stupidly high end audio, but at $2500 they are better than anything out into the $10k range. the whole line from high, mid, and entry matched others way beyond in price. Changing from the good cable down to mid level the price differential is only a few thousand dollars but you felt like the system was changed to components costing $30k less, the speakers which are glorious Meadowlark Nightingales that are as good as $80k Wislon Audio sounded like I'd dropped to $3000 speakers. Dropping to the entry which was actually competitive with $1000 I/C's for $129 and the system exhibited none of the massive audiophile presence and staggering detail and the right there in your face live feeling. So a few grand kills $60k worth of equipment as seen from that angle. Now I take the other way, nice entry grade performance equipment that matches to higher priced gear. Rega Planet, Belles 150, belles 21-A preamp, Meadowlark Heron speakers, a few grand in modest but excellent equipment. As I work up in cable grade the mid that was $300 for I/C's but would outperform most $1500 cable made the low grade in the big gun system sound less clear and detailed, the subtle things were not in the big system that the entry was starting to catch. The $800 I/C's in the entry trashed the big system with entry and the mids didn't have as much closeness and presence but the detail was starting to come through but didn't match the entry with cable that compares to anything on the market.
Questions about how much to spend on cable don't compute because the value with improvement to cost is so far beyond equipment gains it's like it takes $100 to get the gain over a grand in equipment does and it gets worse when the equipment is five to ten grand a component. A few hundred gives a better improvement than ten grand if wire hasn't been addressed much. Starting with the basic decent system I was talking about and entry grade wire you could make all wire upgrades until you were at a high level at which time your equipment upgrades will start giving up much higher levels of performance because you will hear it because the cable is capable of passing higher levels of detail. I started out a customer with the degree of equipment he wanted and educated them to several grades of wire so they knew where improvements were best made. I am writing a book on system synergy because this subject is the most bull filled in existence. I go through the logic in a manner that even Trelja could understand if he could consider for a short period that there is someone who tried $400k worth of wire in hundreds of thousands of dollars worth of equipment and that he may be mistaken about cables over $250 that he has never tried. I'm not sure how guys that find the magic $250 cable come to the conclusion that there couldn't be a better cable. The fact is that as good as they thought that cable is there are many more jumps up from there and they are just as amazing every time you make that improvement.
I cover things like which cables make the most difference and explain why so you can better understand why it's possible to make an upgrade that you won't hear much difference until you improve other things first. Another great thing to know is what happens when you upgrade speaker cable before interconnects.
Starting with a basic system upgrading components looking for great sound is only giving up a fraction of the quality the better equipment is capable of. Cable is a mind blower every time you jump up in quality, then equipment upgrades start delivering detail and presence that makes it worth doing.
There have been some very good responses to your inquiry but they weren't the ones that thought the idea of low limits being as good as it gets. Good quality sound is determined by the wire. Look at entry cable as cutting off 30% of the quality, higher grade lets you hear more, and every cable upgrade lets just a bit more. Yes there is a reasonable cutoff point but it really has more to do with how much you want in your system, picking a point to quit with wire doesn't make sense until the money spent on a new equipment upgrade will not make the difference wire will. If wire would still make an improvent that is just being wasted on new equipment.
An example of an opinion that means nothing is the guy who says that the best budget cable is Transparent, how many has he tried? It has to be the $129 JPS which will beat the $1500 Transparent, the $300 JPS beats Transparent out to $4000, and the $800 JPS beats the most expensive Transparent. I have had all these cables in systems and I had thousands of dollars worth of Transparent I used to show people the value differences out there.