Is Solar panel big enough

I am about to take delivery of 2020 Autosleeper Bourton which has 80 watt Solar panel fitted with a 90amp hour leisure battery.
My previous vehicle had 120 watt Solar panel and 100 amp hour battery. 
We regularly camp without electric for 5 nights. Will the smaller Solar panel and smaller battery cope with this?
Any comments gratefully received.
Regards
Jeff

Duo with 120w 110a ordinary battery, no problems non ehu, bypass Sargent system with mppt and shut down when not needed.

80w panel and 110amp battery here, no problems at this time of year.
Had 80w and 75amp battery on previous van (Nuevo) no problems then either.

Jeff
the solar system fitted is good for the sales person to say it has solar fitted but that's all. it needs some mods to get the correct use from whats fitted.in the summer just 1 x 80w may be ok . I have 2 x 8ow panels new better grade then was fitted and keeps my camper charged all year round and a daul mppt solar controller that charges all my batteries and is wired direct to the batteries .I have 2 x batteries 90amp hour to have the power to run my inverter and run any of the 240 volt items in the camper ref microwave the kettle in the day time with the solar power I get