To answer your question Crispin, they are vintage Austin Seven's (A7), the red open top is a 1927 model often called a Chummy. With the saloon being a 1929 version, referred to at the time as a Wide Door model and favoured by the forces.
Despite their age they are very usable cars, I do about 2500 miles a year with them, and that is out with the worst salty road condition season. Although I personally do not enter into trialing there are many people that use the A7 to both hill climb and trial in some appaling muddy conditions. They remind me of early day greenlane and trial devotees, done often in connection with the Vintage Sports Car club (VSCC).
I will stop now before I out stay my welcome, but suffice to say there is a lot of detail I could share, including some interesting long distance runs undertaken recently, e.g. Peking to Paris.