I don't think there is a best per say but from my testing it all depends on the purpose and the price you want to spend. The add on ones are great and nothing will be as good as glass but I don't mind the digital scopes. I have grown to really enjoy them of course at max magnification you will get a pixilated image. I have tried many and currently have 3 dedicated scopes no add on but the atn 4k pro 3-14 with abl does really well on my low power stuff since it will automatically adjust the reticle for that distance but its heavy I use a tripod so weight isn't an issue. The pard 008 is one of my favorites built in IR, laser, uses a 18650 battery, light weight and compact. The field of view is not good and it has limited magnification range 6.5x and 13x thats all but again it serves a purpose for me. You can get the newer version with built in range finder and ballistic data. If you are ok with the IR not being attached and don't mind holding over/under but still want a small package the wraith mini does a really good job as well it just doesn't have the longest battery life since it uses cr123 batteries so you can use a battery pack for extended use. There are a few others I have tested and if you want any other information usage videos just let me know.