Below I have tried to list some of the pros and cons to the Floyd Rose tremolo unit and in some cases how to avoid or deal with them. If you can think of any others that I need to include, please contact me about them. I hope these help you out with understanding your Floyd unit better. 8)
1. The guitar, when set up as a floating system, will not stay in tune if you ever break a string. This is just pretty much the nature of the beast, unless you want to flush-mount the unit or "block" it.
2. Sometimes, especially with larger gauge strings, the rest of the strings will go "sharp" when you do a string bend. I have been told that you can put a "trem-setter" in the spring cavity of a Floyd equipped guitar to eliminate or lessen this problem.
3. The plating on the original Floyd units is not that durable. The saddles have many porous spots which are prone to corrosion. The base plates, especially on the low "E" side, has a tendancy to rust fairly easily, also. I have noticed that the black finishes seem to hold up a bit better than the chrome, and I have no experience witht he gold plated ones.
4. The baseplate pivots on the mounting posts by two "knife-edged" sections on the baseplate. It is said that the heat-treating does not penetrate very far into this region, and if you lose the edge and get a flat spot, it is pointless to try to sharpen these edges, because you are only removing the heat treted area and it will mushroom out quicker the next time.
5. On most Kramers, the mounting posts are wood screws, and depending on the type of wood, have been known to twist in the wood resulting in a "wollered-out" hole for the posts and the posts will lean toward the neck, throwing off the intonation. The ones with the threaded steel insert, like on a Jackson or Ibanez, have also been known to twist and pull-out of the body and crack the body of the guitar.
6. With the early trem arm assembly where there is a nut assembly which is under the baseplate, they have a tendancy to loosen and they are a pain in the neck to get to to retighten, especially on one that is recessed. The non recessed ones, I have simply used a 9-volt battery in a sock and put it under the string lock screws so I can get under the baseplate with the nut wrench. Failure to do this, and trying to tighten it without a support, can result in the Floyd coming down on the wrench and taking a chunk of finish and wood from the body. There are also products, such as the "Tremlok" that are supposed to do the same thing. The newer style arms are much more user-friendly.
7. Key point to remember about the locking nut, the clamping blocks are designed with a slight radius on the underside to mate with the curve on the nut. If you rotate the clamping blocks 90 degrees, one, or possbily both of the strings will not be held tight enough.