Our band did a weekend gig at a very small bar (we're a 5 piece). Having looked the place over prior, I opted to bring just one amp to try and keep the set up space and "squeeze" to a minimum.
In smaller venues we don't, as a rule DI through the front end.
Normally, I will use my Rick TR35B(15") for all keys, and I use a Fender 112 Deluxe (90 watt) for guitar. I chose to bring just the fender, thinking it would handle everything just fine. Although power wise, there was no problem, the single 12" just didn't have the bottom that I normally desire for piano and particular for a lot of the synth (T3) work.
The next night I brought along my Rick and the sound I wanted was there once again.

...Lesson Learned

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...shboom