Responding to burkecutlery's criticism of the Shapton Pro 5K:
1. "Hard to flatten." I disagree. I use the DMT Dia Flat Plate, and have no problems. Sometimes use an Atoma 1,200. In fact, after initial flattening, I have used just the Atoma 1,200 grit. Moreover, this is a hard, slow dishing stone.
2. "Loads almost instantly(nice combo with being hard to flatten)." Again, I disagree. In the directions that come with the stone (oddly, nobody seems to read the directions) Shapton states that if you have this problem then the stone is too rough, and you should resurface the stone with a finer abrasive. Try the Atoma 1,200, which I use for Shapton Pros higher than 5K.
3". Feels so slippery it's like sharpening in midair." Your stone is probably damaged. As the directions point out, the Shapton Pros can be damaged by leaving the stone soaking in water for more than 30 minutes, or by being exposed to detergent. The directions also state: "if one also uses a wooden support for the stone, and that becomes wet in use, the stone can suck moisture from the wood, keeping it wet longer than it should be. If the stone is too soft, one must simply grind down to a firm surface. Sand the soft layer off with a coarse sharpening powder, rinse and clean the stone thoroughly with water, and then use a finer silicon carbide powder to finish the surface. Afterwards, allow the stone to dry and store the stone in its plastic box." The slippery feeling can be avoided by using the plastic case that comes with the stone, and by making sure the stone does not stay wet for extensive periods of time.
4. "Leaves an edge so slick that it runs on everything, which is absurd for a 5k stone." I'm not sure what you mean by this, but, as I said earlier, the 5K can be used for a finishing stone, so if it leaves a slick edge, isn't that the goal of a finishing stone? Most people want a slick edge after sharpening. If you want a toothy edge, stop at a stone no higher than 2K.
5. "It does not sound different when you hit the edge, so you don't know where you are without checking over and over." I must have really good hearing, because I can both feel and hear it when I hit the edge. Again, your stone may be damaged, as indicated above. In any event, I have not had this problem.
6."It leaves an awful looking finish on a single bevel." With the exception of the new Nubatama Bamboo 1,200 and 2,000 grit stones, synthetic stones leave a synthetic looking finish on a single bevel knife. The look of the finish does not affect the performance of the edge. If you want a traditional finish on your single bevel knives, I recommend the Nubatama Bamboo 1,200 and 2,000 grit stones, followed by finishing on Japanese Natural (and enjoy carrying those bricks in your kit....).
7. "It's expensive." I disagree. If properly cared for, this stone lasts a long time, perhaps a lifetime, especially if it is a portable stone for your kit. You are paying, in part, for a system, and for convenience of having a stone you can carry anywhere in a kit.
8. "It's useless for blending Hamaguri bevels." Like my answer in 6 above, synthetic stones are poor at blending Hamaguri bevels, but the sharpness of the knife is not affected. Again, if the traditional Japanese natural stone finish on a Hamaguri bevel is important to you, then sharpen with a Japanese naturals, and enjoy carrying them in your kit.
9. "It has no range at all--a one trick horse." I'm not sure what you mean. It is a 5K stone. If you want a stone that varies in its characteristics then you have to go with the Nubatama Bamboo stones I mention above, or Japanese naturals, which produce a mud, which in turn changes the characteristics of the stone as mud is produced, or as mud is washed off. The Shapton 5K is, in fact, designed to be one stone in the entire series, and Shapton recommends that you sharpen through the series, progressing from coarse to fine. This compensates for not having a stone that produces mud.
10. "It's an ugly shade of purple." Women like the color, and they are what matter, unless you are gay (and even if you are gay, you may still think that women are the ones that matter).
More seriously, I like the color coded system, including the plastic cases, which make it easy to grab the right stone without a thought. The color coding is designed for convenience, and there are only so many colors in the rainbow.
I stand by my recommendation of the Shapton Pro as an outstanding stone, especially as a stone that can be carried in a kit, along with a courser stone, such as a 1K, 1.5K, or 2K Shapton Pro.