This is the biggest advantage of Tubulars today, and the reason you're seeing some resurgence in their use. Deep dish CF rims can be substantially lighter in the tubular versions.

If you're planning on using conventional aluminum rims, there's not a big weight advatange going Tubular, and the other advantages (handling, pinch flat resistence, and ride comfort) are fairly marginal.

In the end, however its a a subjective judgement, and in part depends on your hassle tolerance.