Beattee had one good season mate in his career, and we signed him off the back of it? Saha was a crock and massive liability as a first choice striker. Remember when he finally signed a contract and then didn't score for months on end? Or when he didn't score for months before he left? All the times he was injured etc, all the makings of a poor investment for the course of the contract, although when we got the real player, he was great.
I base valencia elsewhere on the fact that a club who struggled for strikers and still do to a fair extent, still felt the need to get rid of him. He could be boss here, and i hope he is. But same way as signing any other player out of favour elsewhere around us, the club don't feel they are good enough for the level we are already at.
The difference between gueye and valencia is that gueye was (much like kone) plucked from france from a league that very few people seem to pay attention to and it turns out he is quite good. Same as kante/kone/marhez and the like. Valencia on;y appeared on anyones radar because of the world cup, he played in mexico! He did well for ecuador and then West ham bought him off the back of that. Once he got adjusted to the league he got worse, injuries meant he couldn't get himself back to the level he needed to play at.