Lovely bunnies, great names and what a great set up you have there.
as for insurance, my two are with pet plan. widget has glaucoma so has to have regular eye drops that are £50 a bottle, for her, it is well worth it. Sprocket has also had health issues including an emergency trip to the vets which pet plan also covered. On the flip side, if you are lucky and your rabbits have no long term health problems you could end up paying in much more than you get out.