I have been a long time planted aquarium keeper and I had a reef 8 years back with mixed results. I think it is safe to say that both types of aquariums can be tricky.
I am super excited because I am going to give the reef another go and I just ordered a 140 gallon tank form Envision Acrylics.
Here is a pic of my current planted tank. This version of the tank went through a year of total fail until I got my act together. It is all about CO2, a simple splash of fertilizer and iron from a bottle almost daily, and water changes with light gravel cleaning. Once the plants hit a certain point it gets a lot easier to manage but it can get ugly fast.
Full blown reef tanks are far more complicated for all the reasons everyone knows. If a planted tank goes bad it is not a big deal to replant from zero. If a three year + reef tank has a problem starting over is an entirely different thing.