Red Hat is a company. From time to time their marketing needs run counter to technically defensible decisions, or what the community might like. This happens rather rarely since they long ago realized the value for them of being very supportive of open source. (They realized this before the term "open source" was cointed.) But it does happen, and as a result the default installation is insecure, their network system is not the greatest, and there is no oversight to keep dependencies and conflicts between RPMs straightened out.

By contrast Debian has no such pressure and has to coordinate a disparate group of distributed people. Which means that they have a well-thought out policy. At any given time, most people have some instance of policy to be unhappy with (the resulting slow release cycle is a favorite), but it makes for a much cleaner organized system and means that over time a Debian system tends to stay better organized than an RPM system. This is something which RPM-based systems could do as well, but none actually have. As a packaging mechanism, RPM and .deb are pretty similar. What differs is the community behind them.

That said, if you need a smoother "out of the box" feel, or better marketing, or other things that companies do well at, you are going to be better off with Red Hat.