Important question to ask is whether you can use "classic" insurance or not. Generally it requires that the car be driven only "for exhibition purposes", possibly with a mileage limit per year, and kept in a locked garage. If that works for you, then either Hagerty or JC Taylor is the way to go. Rates are much lower, and they are "agreed value" policies, meaning that they will take your word for how much the car is worth and pay that much if it is damaged beyond repair.
Since I use mine as a daily driver, I can't use "classic" insurance. Instead, I have a "stated value" policy through Mercury (who also handles my other cars and house). "Stated value" means that I define how much insurance I want, but in the case of a total loss, they will pay the lesser of either that figure or what it costs to purchase a similar car in similar condition. I have been very happy with them, in spite of the fact I was somewhat underinsured (my fault!) when my TR3A got totalled. Since the accident was not my fault, they gave me the option of taking the full insured value or fighting with the other guy's insurer. I took the first option and they just wrote me a check for the full amount; letting me keep the car (with it's undamaged overdrive, TR6 gearbox, alloy flywheel, sway bars, rebuilt carbs, etc.)
They also gave me a list of "comparable" cars that had sold recently, which I really appreciated. The average of the comps was $9200, back in 2005. These were cars like mine, reliable drivers but not show cars. I could have disputed any or all of them (for example, most did not have overdrive or synchro 1st), but since I was only insured to $8000 there was no point in doing so.