I love the Uigeadail, but I also far prefer Ardbeg 10 to Lagavulin 16. I suspect that you would probably like the Lag 12 better.
On the other hand, the sherry sweetness and depth in Uigeadail might just be what is missing in Ardbeg for you.
Therefore, you should buy the Laphroaig.
Well, especially since you haven't had any Laphroaig yet.