It comes down to what you feel you can accomplish. If you want the "no holes" guy then you'll sacrifice a year of training. If you want the extra year of training you'll give up a starting build that may be more balanced.
I say go with the 18 y/o. If all else is equal, you'll just have to train where you see as holes. Once you do that, with an extra year of training you'll have much better TSP and a better build.
I have 1757 players for sale and I'm $25,835,360 in debt. Buy them at outrageous prices, or be selfish and make me go bankrupt. You decide, BB.