I haven't stayed at Labriz (although I will be soon and have also been to silhouette island itself) however I've stayed at Mango House twice.

I would say they're really different things, Mango House is a more luxurious hotel in terms of furnishings, service etc. and it's located in Mahé albeit in the south, so it's a bit of a destination itself but you have the option to explore the main island. On the beach front the Mango House one isn't what you think of a normal Seychelles beach as it's man-made.

Labriz is really a destination only, you are on a small island with a few hikes and beaches but it's definitely not a base to go exploring. I'm still excited to stay there though (after 4 nights at Mango House 😉 )

Hopefully that helps, happy to answer any other questions you might have about Mango House.
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