I use Chessbase Light 2007 for researching openings in my CC games and compiling databases. For analysis I used Fritz 6 running the free Rybka 2,2n2 engine.
I’ve also tried Chess Tiger, Shredder, Rybka Dynamic and Rybka Human engines. I think the Rybka 2.2n2 version plays the soundest chess. I have used all these engines in CC events at
IECG/Lechenicher SchachServer where engine use is legal and have not had much success…scoring slightly under 50 percent. The reasons are probably threefold: 1) I have an older, slower computer 2) I did not let the engines run more than 2-3 minutes when determining a move. On occasion I played moves other than the engines first choice if I felt its move was not going to lead anywhere. 3) most opponents were using either Rybka or the latest version of Fritz.
I did recently purchase Fritz 10 which appears to be the strongest of all. It has a bunch of color coded arrows that shows “plans” and “key squares” which I found annoying and of little use so switched them off. No engine is going to be of much help in showing you strategy and plans nor will they be perfect in the ending unless you are using table bases. Even he slightest tactical error will be punished though.
All things considered my preference is CB Light for research and db work and Fritz 10 for analysis and printing out games.
As I said, most players at IECG either run Rybka or Fritz 10 (or 11) and they are the engines of choice for CC GM’s and IM’s who routinely use engines for game analysis. The trick for being successful at that level is knowing when engine output is incorrect…something that is beyond the ability of all but the strongest players.