I have worked with many RDBMS engines (including DB/2 and Oracle) and they are all very powerful things.

There is really no reason to prefer one over the other in regards to what you are wanting to do.

The only thing that no current RDBMS handles well is actual "rollback" in terms of a "re-org" (normally a DB "rollback" is actually just restoring a backup and then "rolling forward" the newer txs from the log).

AFAIA no modern DB can do this (although I do have a design for exactly this).