Your Disco will pull just about anything so it is really a case of personal choice; both single and twin axles have their own advantages and disadvantages.
For neatly two years now we have had a single axle, 6 berth caravan which is just over 7m in length which has been very easy to manoeuvre both by car and by hand, but we now want a fixed bed caravan and the best layouts seem to be on twin axles, which I've been told are a slightly better tow but more difficult to manoeuvre, so get a motor mover fitted but this adds weight! But since I have no experience of these twin axle caravans perhaps someone with experience of both types can help us both out with this one.
As for punctures past, I've been luckily enough not to have one but when I did my caravan tow course they did say to look after your tyres and watch out for the date on the tyre wall, ideally never let a tyre go pass three years of age, even if the tyre looks new. Tyron bands are also worth while fitting they can help control the caravan in the event of a problem