Golf club fitting addresses these different factors
1. The club length
2. The size of the grip
3. The golf club lie angle (very important) The sole of the club head needs to be flat on the ground at impact with a square clubface. If the clubface is square but the toe is high or the heel is high, the ball will still go left or right. A toe high impact makes the ball go left and a heel high impact makes the ball go right and the more loft is added with a higher lofted golf club, the more the effect of going left or right.  Just because the clubface starts out flat on the ground at address doesn’t mean it will stay that way at impact because the centrifugal force straightens out your left arm and the weight of the toe of the club head flexes the shaft upward in the middle pointing the toe a little farther away from you at impact as the toe of the club pulls away from you. At address, the toe needs to be up just a little to start with. If having the toe up at address makes the club feel like the handle is too low and you’d prefer the handle to be higher, then you need a club with a different lie angle. Club heads can be bent to change the lie angle by someone experienced in custom fitting clubs.

The problem with having incorrectly fitted golf clubs is that you'll assume that the bad shots are the result of a bad swing and then you'll start to alter your swing to try to compensate in your effort to hit good shots. What that can do is take a perfectly sound golf swing if you already have one and cause you to start swinging incorrectly while trying to make the golf ball go where you want it to using the wrong golf equipment.

Whether you choose brand name or cloned golf clubs is unimportant compared to the specs listed earlier.

Having golf clubs fitted to you will give you additional confidence that when you have a good swing, you will be rewarded with a good golf shot.