I use my 1989 4/4 as a daily driver from March 1st till October 31st.
I avoid (as much as possible) driving during winter time because of the very corrosive road salt spread on the tarmac. In my country, Belgium, the weather is as uncertain as in Britain, so I scrutinize the weather forecast several times per day to know beforehand whether I have to erect my beige vynil roof of fit my beige tonneau.
As erecting (including unscrewing the door panels & stowing them behind the seats, plus fitting the tonneau) or collapsing (same applies to doors & tonneau, but the other way round) the roof takes about 12 minutes, I tend to drive often with the roof up & the doors stowed away behind the passenger seat.
I was often caught in a shower with the doors down, but water ingress is minimal, even when parked.
Here are a few tips for an every day use:
° I always have a shopping bag & a 6-wine bottle holder stowed away behind the passenger seat together with two fluo emergency jackets and a small foldable emergency triangle,
° a kitchen towel sleeps in the passenger door together with a small pack of paper tissues to jam between the roof & the upper windshield frame when it pours,
° a pair of sun glasses, smartphone earphones, a small flashlight and a foldable roadmap of Belgium sty in the driver door,
° two pocket-size collapsible umbrellas are stuck underneath the driver seat
° two waterproof K-Way jackets & trousers are stowed in their bags under the passenger seat. Believe me, these K-Ways are very useful as my wife & I have often been caught by surprise in a rain- or thunderstorm when driving with the roof down.
Hope this helps & enjoy your Mog!