All offering different things!
First I would take out FPJ from the list. Their watches are stunning are are truly beautiful, but you buy 'off the shelf' so you get what they offer. You cannot go wrong with an FPJ, but it is the least 'independent' out of the list. The other 3, you can get a piece made for yourself and have an input into the concept!
So from the other 3, they all offer something different from each other and again have pros and cons. RWS, you have to be willing to accept the looong waiting time and like his particular finish/design (my personal preference on looks is more swings towards KV/RG), but you will end up with a wonderful piece. With KV and RG, you can get involved with the whole process (more so with KV) and have your personal input into the dials, hands, movement finishing, etc, etc, etc.... this I found with KV was very rewarding and you end up something very special which is just yours.
Have you considered Gronefeld too? Stunning watches, amazing finishes and again you get something special just for you.
All of the above are really nice guys... just ask the questions and one will click... you can then start on your route. Just keep us posted on it

Cheers
Andrew