@SIFI on this I think Alli is possibly the best one to monitor FI wise. What's reflective in his price now is that he's not suited to the PB matrix and no he's pretty much a known quantity.
Where I see the upside is I think Southgate will pick him, he's not fancied Madison so far and despite Grealish being the best out of the 3 (for me) he played no part in the qualifiers. Southgate has shown he will pick the players he trusts and part of the group in the build up, I don't expect that to change in the Euro's this year.
Additionally spurs are in transition, if they don't make the champions League there's every possibility of transfer spec for Alli over the summer.
I wouldn't be buying or topping up on Alli right now but I'm monitoring it between now and the Euros.