Neoprene drysuit (Waterproof D10) undergarment choice

[Frencheese]

Hello folks !
I recently got a Waterproof D10 drysuit that fits me perfectly. I'm planning on diving with it in the Seattle Area, where the water is around 46F, up to 54F if I'm not wrong.
Since I was used to dive with a Vulcanized Loitokari drysuit + rental undergarment, I struggle to evaluate the thermal protection the D10 provide and how much should I "add" to be warm enough as I used to be. I saw a lot of topic here, talking about Seaskin (T2 Multi Sport), Lavacore (Backzip Suit), Bare Exowear.. Since I don't have much space in the suit, I thought they would be a nice pick but are they gonna be warm enough for Seattle cold water ?

Second question ; I usually dive in Hawaii in April. I thought that the Seaskin / Lavacore suit would be useful for diving there ? Or should I just use the D10 drysuit as it is (I m VERY sensitive to cold. I usually wear a Surf spring suit for snorkeling there).

Sorry if those questions has been asked again and again.. this kind of gear can be quite a budget

 

[USdiver1]

I have a neoprene dry suit that I use in water down to 36F. Besides a bathing suit I have no need for undergarments to stay warm.

Weights are another issue, as my suit is very bouyant and requires quite a lot of lead to get me down.

Overall positive on the dry suit: an added benefit is in case of leakage it becomes a wet suit, not a water soaked diaper inside of a baggie like a flooded trilam.