I would've liked to have given Wilson a bit longer because from what little I saw, there is some talent there but as you say, that's quite a hefty price for him.Lankshear £1m from Sheffield United (who acquired him from Woolwich a year previously as Lankshear refused a pro contrat there) .
At Sheffield U, Lankshear captained their u18 side and was record top scorer, albeit in the next tier down from PL U18 that Spurs play in.
Wilson has done a bit more in a SPL (which is more comparable to L1), but only looked 'ok' for Spurs u21's not 'wowing' them, which is why £2.5m seems OTT.
It's quite hard to settle and impress in a few short months unless you really are something special.