One of the things to consider is availability. Is the Grelot immediately available ? The WIlliams SRP LE has a waiting list. Robert sends them out first come first served. There will only be 200 SRP LE razors. I know RW is up over 100 but not sure how far. He is easy to communicate with. Send a PM to Papa Bull or and email and ask how long the wait is unless you want it now. In that case the Grelot might be the way to go.
I've got a couple of vintage Grelots and I have the RW SRP LE. If I could only keep one or the other I would opt for the LE without thinking twice.