It depends on how much power you use and how much room you have on a TC for solar. Any amount >100W is helpful.
I'll relate my experience on our 11-1/2 week trip to Alaska in 2016. This was in a small 5th wheel with 370 watts solar and 440Ah battery bank. Average usage was 70 - 80 Ah per day (couple of hours TV/DVD; some microwave, coffee pot, toaster usage; CPAP every night; lights in summer in AK, not so much).
I have the capability to 4-way tilt the panels but I only tilted once as we moved fairly often and much of the time it was overcast so tilting was of no benefit. Many days of rain. Travel days were typically short so not much charging took place from TV.
Through all this solar kept pace and we only ran the generator eight times for a total of maybe 16 hours. We had electric HU five nights. One night was in BC and doesn't really count as it was on a 15-amp extension cord that quit some time in the middle of the night.
For me solar was a huge success. We could have been more conservative with power usage and probably eliminated generator use altogether.
