Unfortunately, that clickbait article isn't very helpful. Not picking on you
@J.R. I'm in the insurance business and I'm pretty familiar with this segment of it.
The first two insurance providers on their list exactly the same policy (they are both agents for Markel Ins. Co. The underlying policy and rates are identical). So... no reason to differentiate them other than to provide the two different paid links on the page.
The third choice is touted for high limits, but McClain is only available in 5 US states. They're also a small local insurance agency with one office so forget about stuff like online policy service or quotes.
The fourth choice is Sundays Insurance. Before you ever give that company your money, read their sample insurance policy and then compare it to its competition. Just for starters it is Actual Cash Value so expect depreciation. And read the Exclusions list and think through what they have put in there. Also they only cover recreational use, so if you use the bike as transportation (i.e. commuting) or for utility (shopping) its an unanswered question in their policy language whether you are covered or not.
The fifth and last one on their list is another Markel agent. So, exact same policy and pricing as the first two.
I personally have a Markel policy written thru the Velosurance agency.