It really is a matter of personal preference. Samsung's custom user interface TouchWiz has a LOT of added features compared with "vanilla" Android (i.e., what you see on the N7). Depending on the person, those features might be the best thing since sliced bread, or they could be a whole lot of extra stuff that is never used. Downsides include extra storage memory taken up by TouchWiz (e.g., a 16 GB Galaxy S3 or S4 only has about 8 GB of internal storage available to the user because TouchWiz and Android take up 8 GB themselves), and for some Samsung devices, somewhat choppy performance if the processor isn't powerful enough. Also, these extra features can't be removed.
The best thing to do is to try it out for yourself!