I have never used laterite. No opinion on it one way or the other. However I have just started a 150 planted tank with the idea of going fully planted. I used purely SMS and the plants are loving it. I am really pleasantly surprised at how well they are doing. I placed a few fert tablets around the substrate where I thought a plant would look and they are doing exceptionally well, especially considering the lighting I have is not that great.
I have two 3' fluorescents on the go at the moment for about 14 - 16 hours a day and the plants are really taking off. I am also looking at buying a couple of T5's just to up the ante somewhat. Then once my pocket book recovers from the shock I am going to look at a pressurized CO2 system. *If* I feel they need it that is.
Just my 2 cents