For $65 you really can't lose
The wheels are the right size for roller derby but they are just too hard. You will find it difficult to maintain control in the corners of the track. For derby it is really important to get the right kind of wheels that have lots of grip.
Most people upgrade to higher end boots because they get better performance out of them. The lower end boots are designed for recreational skating and don't provide the energy transfer needed to play your best at roller derby. With boots like the Targa, you tend to get some shifting of your feet inside your boots. This makes you lose speed, control and causes blisters. They are also heavier than higher end speed boots.
The higher end boots like the 125 or 265 are designed for speed skaters and other track skaters. They are super light weight, fit like a glove and provide amazing energy transfer and control.
I find that entry level skates are good for beginner derby skaters because they don't often appreciate the features of the higher end products. It does mean that they eventually upgrade once they have become better players and are looking to improve their performance.