It really depends on 2 factors as to whether to use a kit. Time and access to fresh fruits. It definately takes more time to make wine from fresh fruit as you have to prepare the fruit, then balance the sugar and acid. You also need to get the best fruit you can, as the better the fruit, the better the wine. In addition, the cost of fresh fruit can be more expensive than a kit. Most of my customers that make wine from fresh fruits have access to cheap fruit, i.e., Mulberry trees in their front yard, someone gave them 2 bushels of peaches, etc.
The great thing about a kit is that the preparation is done for you. All you have to do is add water and let it go. You also do not have to worry about consistency, as you will always wind up with a very good, if not great, bottle of wine. Starting with a kit will also help you learn about yeast, racking, stabilizing and fining. All steps you will need if you make wine from scratch.
The bottom line is that a kit is a great way to get started. Once you have the hang of the kits, you can branch off on your own.
If you have any questions, the users of this forum are very good with their answers. If all else fails, you can give me a call. My contact info is all over my web site.