Hi!
I prefer the Dutch side anchoring in Simpson Bay.
Customs and immigration are inside the channel. You anchor and dinghy in.
If its rolly go inside till the sea settles. Its good swimming in the bay, not good in the Lagoon.
Cost is $20 per week for a 40 footer.
On the French side its $10 to clear in Marina Royal, much more to clear in at the ferry terminal at Marigot. Anchoring is free inside the lagoon on the French side, but its further away from everything.
Its a personal choice
Hope this helps
See you when you get here!!
Mark