Yes, that's right.
For latency lower is better.
Column Address Strobe (CAS) latency, or CL, is the delay time between the moment a memory controller tells the memory module to access a particular memory column on a RAM memory module, and the moment the data from given array location is available on the module's output pins. In general, the lower the CAS latency, the better.
Aida64 is for general hardware and Maxxmem is specifically for testing RAM.
Not really sure but, my guess is Maxxmem should be more accurate.