I bought the Spin Doctor set from Performance a few weeks ago. I picked it up for $39 with a sale that they were having. It looks like the same took kit rebranded. I have some Park tools that I needed that were not in the kit. Clearly the Park tools are better made. However, if you are using these tools on your own bikes, they will get the job done. I am a diy type person so I have a lot of tools anyway. Most of the hex wrenches and screwdrivers are already in my tool boxes. For the price, it is hard to beat though.
I am normally not one to buy cheap tools. I use my home tools a lot and I tend to buy Bosch because I know what I am getting. There are some tools that you do not mind buying from companies like Harbor Freight because they will be used infrequently. For me, my bike tools are like that. I am in the process of changing out my groupset on my mtb. I have not had reason to do this in the past. My tool kit handled this with no problems. I probably won't use most of these tools for a very long time after this. Thus, you have to weigh out the investment. I do not work on others bikes so it was not worth buying all Park tools.
As for your question about the price, many of those are the same tool kit just rebranded.