Possible problems in mixed use of apt-get, aptitude and synaptic

Even though aptitude and synaptic are both front-end to the APT (and I myself stick only with apt-get), peculiarities in each of the available dpkg/APT frontends seem to cause problems and confusions when they are used interchangeably. Beginners especially -- who tend to do copy & paste more often, thereby executing apt-get and aptitude commands more or less identically -- may find some situation puzzling.

Please list the possible problems that might arise when they are mixed up and tips to avoid when one has to rely on multiple packaging managers.

For what I know, different package managers can have different opinions about which packages are installed automatically, or at least it was true time ago, not sure if it is yet so.

This can have consequences on autoremove subcommand (be aware that aptitude does not have an autoremove subcommand, but executes autoremove automatically).

So one can have unuseful packages hanging around, not a big problem anyway.

Also, they can have different opinion about which packages are blocked, but this should not be an issue for the normal user that often make no use of this feature.

The dependencies and conflicts resolution algorithms are more or less equivalent, so in conclusion I think the user can mix the use of different package manager without the fear of breaking something.

apt-get and aptitude use the same backend really. If something is installing a package using apt-get, aptitude will be blocked and vice-versa.

aptitude is slightly better at resolving conflicts and cleaning up after itself, but it the end, if you use aptitude, synaptic, or apt-get you're performing the same task.. its just a matter of user preference.