3rd the Clear Day plus Paul does allow an in home trial period. These made a huge positive difference in my system. The music became so much more palpable...very well fleshed out.
I do agree with Zd542 about first getting used to the sound with your current cables. I think that is absolutely essential. Also - unless you get lucky (someone replies that has the same gear and room config.) most of the responses (like mine) will be other people's favorite with no guarantee they'll sound as good with your gear or in your room. An in home trial period is key. Clear Day, Morrow Audio, Audio Advisor are good in this regard.
Certainly, take advantage of the Cable Company's lending library if you can, but they don't carry everything (e.g., no Clear Day, no Morrow Audio).
Good luck and have fun. Enjoy your new gear. Maybe even before cable you should consider room treatment (a couple of GIK panels behind your speakers can make a world of difference).