This topic piqued my interest, so I wiki'd recent successful strikers in the Championship and looked at their records at ~19. Its a quick and badly laid out look, and I don't vouch for its accuracy. Just something for interest to get and idea of what Championship level strikers were like at 19.
Danny Graham - now 25 years old, scored 23 in Championship this year
Age - appearance (goals ) club
At age 19 - 09 (2) Darlington
At age 20 - 14 (0) Derby
At age 21 - 07 (1) Leeds / Blackpool
Simon Cox - 23 years old, scored 35 in 62 for Swindon before moving to WBA
At age 19 - 21 (3) Brentford / Northampton
Hard to do it for Shane Long as Reading were in premiership 21 (2).
Grant Holt was not setting the world on fire at Halifax, Barrow and Sengkang Marine? (did start tapping them in for Barrow in next few years though).
Jason Scotland between ages of 22-25 for Dundee 50 (8), not sure earlier.
Kevin Doyle at age 19 - 10 (0) for St Patricks Athletic
Kevin Davies at age 19/20 - 64 (7) for Chesterfield
Riccardo Fuller, earliest I can find is age 21, 8 (0) for Crystal Palace.
Dean Windass at 21-23 was 73 (13) for Hull (did well for North Ferriby United before that)
Jamie Cureton, good season 17 (4) at 19 in premiership, then 17 (2) for Norwich / Bournemouth following season.
But what is your point? Most people on this thread seem to agree that he has potential - or at least are prepared to accept Gus' judgement about a player - but also many suggest that he is not the man we need for next season. He may well go on to be a great player who knocks in loads of goals - but at the moment, would you rather have him in the team for next season or a proven, reliable, established Championship striker? There's no question which you would go for.