Pretty good Holosun sales video if you want to see what your options are in 2021

[Joe L]

I came across this video that covers the Holosun current line of red dots.   
https://youtu.be/WNDyUNtCvb4
I only have experience with the 507c, 507c-x2, and 507k-x2 but it is all been pretty good.  I still use Burris Fast Fire 3 3moa dots on my P-09 and 97 pistols and my only complaint with the Burris is not enough dot brightness adjustment steps.  The Holosun's have maybe 10 or 12 clicks in adjustment, and I routinely adjust the brightness on overcast gloomy days, the Burris has 3 and I wind up with the dot too bright or too dim on gloomy low contrast days. 
Joe 

[bailagent100]

I caught this video a while back, myself.  It is excellent and Luis (with Holosun) seems to really know his stuff.  He's a very knowledgeable rep for them.  IIRC, he's one of their design/engineer types.  This vid is def worth the time to sit down and give it a viewing.

I have two or three of their products, have recommended them to others and I will be buying more of their products. Just a satisfied customer.

[BCHINOC]

I have a 507 and  507 x2.  Love them both

Sent from my moto z4 using Tapatalk

[florida man]

I have a he403c and a he407c gr v2.  The green dot has less flare than a red dot when you turn them up in bright sun.  I’m totally spoiled with the shake awake feature.  Battery on the 407c is going on 3 years now.  Never had any issues with either!