It depends upon what you mean by "sight-seeing".
Last October we traveled on the "Not Recommended for RVs" valley loop road in Monument Valley. Our 24 foot Class C did just fine on that topsy-turvy road with some carefull maneuvering. However, the friends traveling with us in their 24 foot Class C would not try it, so for them at that time at that place a towed vehicle would have been just the ticket.
We go off-road quite a bit with our Class C. "Hate to" are strong words .... but I guess they express my feeling about towing anything behind our RV. I do tow our 14 foot aluminum fishing boat at times - but not off-road, not into shopping centers, not into museum parking lots, not into trail head parking lots, not into Gold Rush ghost towns, and not through downtown San Francisco.
In general we like to have our home with us at all times when we're out and about on an RV trip, as that's what we bought it for. It sure is nice to always have a bed, a table, a refrigerator, a microwave, and - last but not least - a bathroom with us at all times!