I just knew that some smart aleck would take the challenge and post the question. Of course, out of any hundred anglers there will be almost as many different preferences. And, just like religion and politics, there are some who get pretty worked up over their personal choices.
As most previous replies have acknowledged, the type of tackle and types of fishing you do should dictate the type of line you use. For someone who gets out only a couple of times a year, and cannot appreciate the subtle differences in the various line choices, it doesn't really matter. But, once you have fished long enough and seriously enough to be in tune with what is going on at the business end of your rod, there are some real considerations. Most of those have already been mentioned, and will probably get a lot more discussion before this thread is through.
On a purely personal note, I have fished everything from 130 pound dacron, on a 12/0 reel, to 1/2 pound test tippet on size 28 dry flies. In between, I have tried just about every kind of braided, fused and monofilament line ever made...in the eternal quest for the perfect line. My conclusion is that there are many lines best for specific applications...and some that work well over a wide range of fishing situations...but nothing is a UNIVERSAL line.
I have kind of settled into being a light tackle enthusiast. I use mostly four pound line, on ultralight, light or medium light action rods...both spinning and baitcasting. I often hook large fish...sometimes with sharp teeth and gill plates, capable of cutting soft lines quickly. Thus, I tend to look first at abrasion resistance. Almost of equal consideration is limpness and castability...and overall line strength per diameter. Fishing light lures on light tackle demands that you be able to effectively cast long distances, and with accuracy. Stiff, springy lines don't make it.
When I lived in Sacramento, and fished steelhead and salmon in the coastal rivers of California, I loaded my light reels with 4# Maxima Chameleon. It was slightly larger in diameter than my preferred Stren, but held up well when dragged over the rocks and logs found in most of the rivers that held the salmonids. I landed 19 pound steelhead on the 4#, and a salmon over 50 on the 6#.
When I moved back to Utah in the 70's, I used the Maxima on big cats, but went back to Stren for walleyes and trout...and most other fishes. However, I never did like the knot strength or abrasion resistance of Stren. When Berkeley Trilene came along, I tried all the alphabet soup...XL, XT, etc. I used mostly Trilene for about the next ten years. With the introduction of the "copolymers", I tried the Berkeley TriMax and loved it. It was good strength per diameter and it casted like a dream. I could get several trips out of each "top shot" before having to stip off that sixty yards or so and respooling.
I continued to experiment with most of the new lines that came out, including Magnathin and the different lines in the Fenwick arsenal. All had their positives and negatives. I still use the leftovers to wind on the base of my line spools, before top shotting with my working lines.
I have also used (and still use) fusion lines and fluorocarbons. They are excellent for the uses intended...heavy fishing with small diameter and low stretch...and clarity for leaders on the latter. But, for my light tackle pursuits I have used Silver Thread Excalibur almost exclusively for at least five years.
Excalibur is small diameter, ultra clear, casts well, does not have memory (springy coils) and is the most abrasion resistant mono I have ever used. I have landed large flathead catfish on 6# Excalibur that had my jigs well down inside their mouths...which sport some nasty teeth. (I have lost many smaller ones, on heavier line, that did not last more than a couple of head shakes.) I have also landed bass and catfish over 8 pounds, on 4# Excalibur, after they had mowed an acre of rough edged water weeds with the line. Oh yeah, I have beaten up on some big carp that did the same thing, and rolled in the line to boot. And, if I snag up on the six pound line, I have a tough time breaking it off from a tube.
Excalibur stretches more than fusion lines, but not as much as most monos. I have never had any issues with the sensitivity or positive hook setting qualities. Since most of my fishing is in water less than 20 feet, and seldom with any long casts, the stretch factor is not as serious as it might be with trolling long lines, or dropping over fifty feet deep. In such cases, I would either use larger diameter Excalibur, or something else.
I'm not on a soapbox for my particular choice of lines. I offer my observations strictly as a matter of persona preference. I have always been surprised, however, at how few other fishermen I know have tried the line, before I suggested it. Most have sung it's praises once they tried it, in the strengths they customarily used it. It is difficult to find in retail outlets anymore. It did not have the big advertising bucks spent on it, like many of the Berkeley and Stren products, so a lot of anglers have never heard of it...or tried it. About the only place I can find my 4# Excalibur now is Cabelas.
See, Tomegun. You shoulda left well enough alone.