Linux /dev/random is pretty good. For anyone trying to reverse engineer the previous state of the disk it's much easier to substract out all zeros as opposed to a pseudo random sequence. Especially if the attacker doesn't have the pseudo random number generators full state.
Also keep in mind that with SSDs that have significant smarts for compression, trim, deduplication, benchmark cheating, minimizing write amplification, and related. Writing a pseudorandom sequence is more likely to actually overwrite almost 100% of the disk. Sure bad sectors that are remapped won't be, but the rest should.
Even better if you just use full disk encryption and throw away the key. Also the "secure erase" functionality is a good start, but if you aren't the trusting type it's best to wipe then overwrite.
Also keep in mind that with SSDs that have significant smarts for compression, trim, deduplication, benchmark cheating, minimizing write amplification, and related. Writing a pseudorandom sequence is more likely to actually overwrite almost 100% of the disk. Sure bad sectors that are remapped won't be, but the rest should.
Even better if you just use full disk encryption and throw away the key. Also the "secure erase" functionality is a good start, but if you aren't the trusting type it's best to wipe then overwrite.