The Jet has a 21" bed while the Laguna has an 18" bed.
Regardless of the lathe you buy, you need to recognize that the nominal length of the bed and the actual working length are different lengths. The worst case scenario is probably the situation where you hold a spindle blank in a scroll chuck, and then drill an axial hole from the tailstock end. In that scenario, the scroll chuck will be about 3" deep, the Jacobs chuck will be about the same, while the drill bit will consume another 3-5" depending on the bit being used. In other words, upwards of 9-11" of effective bed length will the lost to the tooling, which then limits the actual maximum length of the spindle blank you can work with.
So if you are looking to do longer spindles, you need to be thinking about either lathes with longer beds, or lathes that can accommodate bed extensions.