Information on why devourer is a lowsy item for top lane, or any lane for that matter.
lets say you get 5 kills in laning phase as a solo laner. thats 5 stacks. then you help kill 1 dragon, thats 5 stacks as well. Thats 10 stacks during laning phase, now you need 20 stacks more. NOW throw in how long it takes to hit 2250 gold. you get 1550 gold at 43 cs, which is around the 6 minute mark normally. if youre csing well. so 6 minutes in, you have devourer finished. the only stats you get from it are attack speed, and 30 magic damage on hit.
( This has been checked, at 7 minutes [estimated time of wave clear] you will have between 2,043 / 2,313 the latter being perfect cs)
laning is over in most game by 20 minutes. usually by about 17 minutes. so from 7 minutes, you need to gain 30 stacks worth. 5 kills and 1 dragon is a good laning phase to get from the 7 minute mark until the 20 minute mark right? it doesnt stack on minions at all. so, 10 stacks is taking no jungle camps, jungle camp spawns what every 3 minutes?
(For arguments sake lets say youre on krug side of top lane. ) Krug spawns 1:40 after being killed. So, from 7 minutes until 20 minutes. (13 minutes) you CAN kill 4.85 krugs if you kill it the second you get devourer, and the second that krug spawns every time you kill it. ( impossible). So, that leaves you with roughly 14 stacks on devourer.
5 kills = 5 stacks 1 dragon kill = 5 stacks 4 krugs = 4 stacks That is 14 stacks at the 20 minute mark.
So, that's 44 magic damage on hit, at 20 minutes. for arguments sake, lets say in the next 13 minutes, you get your final 16 stacks. ( For those keeping up, that's 5 kills or assists, 1 epic monster, and 6 large jungle monsters. or, [2 dragons 1 large monster] )
So, at the 33 minute mark. You get 60 magic damage on hit. and a phantom hit every 2 attacks. Is this really worth an item slot? keep in mind you have to take smite to even buy this item, effectively taking away either an escape or an offensive ability, in your summoners.
In my honest opinion, I don't see it being viable on any laning champion.
Thank you for reading.
TL:DR
The numbers don't add up. Now, I know that the numbers are skewed a little bit, and i'm only silver so give me a break, but i'll fix the numbers to exact amounts tomorrow when I've had sleep.
EDIT: most of the numbers have been fixed. I'd like to hear your opinions.