I have recorded bass/guitar via DI, but it's the rare guitar that sounds decent with just its pickups being amplified.
My LP sounds ever so much better through an amp or (if I MUST DI, through a footpedal of some sort --depending on the sound I want).
My bass is routinely routed into the PA when we gig via the line out on my bass amp, which allows me to carry a relatively light amp to the gig and still get a lot of bottom out to the dance floor. The amp sits on a tilt stand, and serves as a bass monitor for the band.
I use a simple Whirlwind Imp II, I think it is, for the guitar; at practice I use one with the bass (my practice amp doesn't have a line out).