AntiCables v. Morrow?

Looking to buy 1st cable upgrade from #10 wire. For Ohm Walsh 100-S3s and Spendor S3/5s running off ATI 1502 Power amp with CJ PV 6 tube preamp and Cambridge 740C. Listen to lots of jazz, female vocals, blues, acoustic music. I found the preamp softened and warmed up my sound taking off what I thought was some edge but as an older amp some detail too. Trying to decide on what kinds of speaker cable to move towards. Cant afford to go truly esoteric...$200 -300 max. Can people give me a sense of the relative benefis or tradeoffs between the two companies and the types of cable they sell?
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Tvad is right regarding price to performance scale and everyone has their own scale. When you trade up on the Morrow Audio cables you could be spending more on the trade up then you did with the original cable you have. Going from SP5 to SP6 would be more than buying another SP5. This is with the best discounts of the year given. At the time the price between these two cables were apprx $260 or so and I went for the SP5 not thinking clearly about the trade up price. Now it is way over and above the price to performance scale for me. You just need to know going in what the trade up price is going to be if you want to do this program. In my system the ic's have been the cable that provided the better improvements for me.
Same here was thinking of upgrading my bi-wire sp-3's, but if it is the sweet spot, Im not touching it they are the best I've heard in my system.
Jdub39, they may or may not be the sweet spot in your system. They were not in mine so you will have to look at your price to performance scale. It was not a huge increase in performance but it was for the better. When I saw the price to trade up from SP5 to SP6 I felt it would be well over my scale based on the other experiences on these speaker cables. Going from SP3 to SP4, I don't remember it being a bad trade off. If you can't hear the differences then just send them back. I use an SP4 and SP5 in my system and bought the SP5 without the trade up program.
I just think the Sp 3's are a good sounding cable in my system and dont want to ruin it , and after changing out just about everything from the power up, the most audiable changes heard next to the Sp-3's where from the power cords and recpticals and conditioners, Ive channged three cords so far all having different effects on the sound. Maybe later down the road I'll give the Sp-5's a try, however I'am thinking of trying the Sp-4 interconnects.