The choice is bewildering. I suppose you need to look at the benefits offered - hospitalisation reimbursement (up to 200% is useful, it means 200% of the amount reimbursed by the secu, which is often a much smaller sum than the hospital bill); dentistry cover; opticians; medicaments and basic tests. Also useful is "tiers payant" which means you don't pay up front and claim back from the mutuelle, but they pay direct - almost always with the pharmacy for example. There are also often limits on how many days reimbursement of treatment such as physiotherapy.
I think you should try and tailor a package to your likely needs. We reduced the cover from an all singing package to a more modest one and saved about 100 euros per month!
The online sites are worth getting a quote from to compare the costs/benefits - but beware of incessant follow-up emails from them.
Do any other readers have advice or suggestions?comments to taglines82@gmail.com