I have been experimenting with different strings for a while and thought I would post my perceptions of them in case it might help others. I have learned a lot by reading what others have had to say and this message serves as a feeble attempt to give a little back. I am an experienced guitar player but relatively new (last year or two) to playing classical. My guess is that I am an advanced beginner to weak intermediate. The guitar I play is a Cordoba C9 with a cedar top. I have left each set of reviewed strings on for at least a month, most of them longer, and I am listing them in the order I tried them. Intonation on all of them up and down the neck was great. It is never easy describing sound, but here goes...
1) Savarez 500CJ - bass strings are bold sounding and do not feel very stiff considering their published tension, treble strings are loud, punchy, percussive, bright, and perhaps a bit cold sounding.
2) D'Addario EJ44 - bass strings are warm and deep, not very loud, and slightly floppier feeling that the 500CJ, treble strings are warm, a bit thuddy, and not very loud.
3) Savarez 500CR - bass strings are bold/bright sounding and just a little less stiff feeling than the 500CJ, treble strings are also less stiff feeling than the 500CJ and a bit less percussive. Overall, these strings sound a lot like the 500CJ with less tension and not much perceptible loss in volume.
4) La Bella 2001 Hard - bass strings are warm, feel floppy compared to any of the above sets, and are a bit dull sounding even when fresh, treble strings are bright but less cold sounding than either Savarez set. Very musical sounding to these ears.
5) D'Addario EJ45 - bass strings are deep sounding but have a nice punch and brightness to them when needed. They are maybe just a bit stiffer feeling than the La Bella's, but easier to fret than the other sets, treble strings are warm, velvety, and sweet sounding (similar to the La Bellas), but are also punchy when needed with some brightness. Also, more than any other trebles, these seem dynamic in that can be quite quiet or loud when you dig in. The Savarez sets were the opposite by comparison, loud but not much variation in volume whether you played gently or hard. The EJ45 are still on the guitar. Overall, they are my favorite so far.
6) Augustine Classic Red - bass strings are warm and smooth sounding, not as bright or punchy as the EJ45 or Corum, the Classic trebles are a bit firmer feeling that the EJ45 and are very sweet sounding with a bit more brightness than the EJ45, but not as bright at the Cristal trebles, The Classic trebles sound great with vibrato and sustain better than any other sets I have tried. To date, they are my favorite trebles by far, though I prefer the EJ45 basses.
6) Augustine Classic Blue - Bass strings feel noticeably stiffer/firmer than the Red basses, and squeak a lot more. They might have a bit more punch than the Red basses, but they are not as bright or punchy to these ears and the EJ45 or Corum. Smooth and deep tone with not a lot of definition, like the Red basses. I already commented on the Classic trebles (above).
So far, EJ45 basses with Augustine Classic trebles are my favorite combination. I am very happy with the tone, sustain, vibrato,volume and feel of the strings, but will keep experimenting.