So I take back the implication that the t400 is not well designed. ThinkPads have a good reputation for hardware design, which I assume is well earned (have not owned one myself). The same cannot be said for all PC laptops. And software is a whole other matter altogether, of course.
As for customization, Apple deliberately restricts the options for customization relative to other vendors. They definitely have an attitude of designing a few models that fit the needs of a many customers, as opposed to many models each appealing to smaller, more specific groups.