I've played plenty of gigs with only a T5 and it worked out great. The preamp in the T5 provides some of the cleanest, high fidelity, most musical sound you will ever get out of an electric stringed instrument. The secret is in how/where you send the signal once it leaves the guitar.
If you are plugging the guitar exclusively into an electric guitar amp, do not expect it to sound like an acoustic guitar. That kind of amp isn't designed to reproduce the highs that you expect to hear from an acoustic. You will, however, get some killer electric tones from the T5. Go into switch positions 2 through 5 and tweak the tone and volume to your heart's content. It takes effects really well too.
Taylor clinician (and all around great guy) Marc Seal, shows off the perfect way to run a T5 at each of his road shows. Take the signal from the T5 into an A/B/Y box. Take the 'A' signal output and run to your Acoustic amp or direct to the PA (via a DI). Take the 'B' signal output and run it to your electric guitar rig. Now you can have acoustic, electric, or BOTH at the same time (which sounds KILLER!).
Because the T5 has a balanced output (like the acoustic ES), a variation on this theme (and the way I do it) is to use a Taylor balanced breakout box in place of the A/B/Y. Use a balanced TRS/XLR cable from the T5 to the breakout box. Use the unbalanced 'TUNER' output of the box to feed your electric rig, and take the balanced pass through signal direct to the PA, house system, or your acoustic setup. To mute the acoustic signal, hit the 'MUTE' switch on the breakout box. My electric pedal board is a Boss GT-10, so to mute the electric signal is kick down the volume pedal.
