It can boggle you a bit!
but honestly its only confusing if you are basing everything on the price. Most names ie, Argos, Tesco, Sainsbury's are large chains branching out to the pet market just to get a slice of the pie. They are not well established pet insurers who know their stuff and cover accordingly. Ignore the cost for a minute, and read the policy cover carefully. Go for lifecover, and vets costs around £1000 (should be more than enough hopefully). If you live in a busy area, you may want to pop theft cover or accidental death.
Personally I would go petguard or petplan all the way, their feedback speaks for itself