As CQBINKALIFORNIA said, Aimpoint is "the best" and is for serious military use. The company makes sights you can bet your life on under adverse conditions and they are priced accordingly. The $90 sight you are considering is for recreational shooting and is probably "the best" for your use.You asked for "The Best".
Aimpoint is the best, take yer pick.
If you look at the Burris XTS-135 for a good example of a single mount 30mm red dot, Burris recommends using their XTR rings which appear to grab and support about 1" of the of the scope body tube. These rings would work fine on a rail adapter, or a scout mount rail. I was just questioning the rigidity of using a single standard Ruger type ring to mount this kind of red dot via one of the integral Ruger scallop mounts such as the YouTube video was showing.The YouTube video shows using a single regular Ruger compatible 30mm scope ring to mount a red dot sight which is designed for single ring mounting. Those single mount 30mm red dots have specialized mounting rings which are much longer along the body of the scope they hold, and are made to mount securely to a Picatiny or Weaver rail. I tend to question if a single regular ring to the Ruger integral scallop mount will offer enough support to mount it properly.