The principle advantage of pre-installed electronics is that the tone and volume controls are easy to get to. But there's something sacrilegous about cutting a hole cut into the side of a multi-thousand dollar guitar and filling it with ugly plastic sliders.

But, if we're talking about Taylor guitars, and specifically the Grand Concert and Grand Auditorium sizes, it's probablly smarter to go with the "EC" (electric cutaway) models. They outsell the regular models by a wide margin and if it ever comes down to needing to sell the thing to buy groceries an EC would be easier to unload.