I’ve got all of them except the HD2010. To answer your questions:
Which ones will give more power stock? Yezl Y3 looks the brightest via ceiling bounce test, but doesn’t throw as far as Courui at stock. The Y3 does come stock with annoying (for me) PWM compared to the other two I have.
Which will have more throw stock? Courui
Which will have an easier host to mod? I’ve only modded the Courui and tried to mod the Y3. I wasn’t able to mod my Y3 because the retaining rings were just impossible to remove (both from driver side and springs, so no braided springs for me). However, the Y3, if you can’t access the driver, the LED is easily accessible and the driver can also drive an MT-G2 if you prefer to swap it out over the XM-L2. I didn’t have any real issues with modding my Courui (thread here ).