Exactly.
"Despite scoring loads of goals Ulloa hasn't been that good". Que? I've been gobsmacked to hear people around me in WSU moaning about his performance, or effort or (unbelievably) his ability to know where the onion bag is. I'm not claiming he's Jimmy Greaves - but he is significantly...
I reckon he's probably behind Rhodes, McGoldrick & Le Fondre as well (in terms of how hot his property is) but agree entirely with you that people with his skill set are very rare and I wouldn't be happy at all to see him go for 6m.