TechTools Pro and Disk Warrior are different animals with different purposes. TechTools Pro is a general maintenance utility suite. Disk Warrior is a file recovery utility that performs its magic by rebuilding the directory structure of your drive. Both of these have excellent reputations of long standing. Drive Genius may be OK, but it is very much johnny-come-lately. That said, if the OP is looking for a routine maintenance utility, then he should reconsider. Routine maintenance of MacOS X is unnecessary and should be avoided. Use TechTools Pro and Disk Warrior to solve genuine identified problems.