Depends on your preference - I really like 6MOA dots - to me it's becoming a requirement increasingly.
The best: Trijicon RMR 6.5MOA
Good: Sig Rome1Pro 6 MOA, Trijicon SRO 5MOA (great to shoot - not quite as robust as the RMR - I have 2 SROs - love em - just not as much for carry)
Good but I have to compromise on reticle - Holosun 508T, Holosun 507C, Holosun 407A3, Deltapoint Pro, Swampfox Liberty, Romeo1Pro 3moa.
Vortex - i don't even recommend because even casual shooters are breaking them though the warranty is exceptional.
Any dot that has an auto-off feature I don't recommend for carry. Most dots with autoadjust I don't recommend - my RMR is useable - but my SROs are not usable with auto adjust. My holosuns auto adjust is hot garbage - fine for a range environment - not fine for a situation where lighting is going to change - like standing in a dark room aiming through a lit doorway.
I just broke my first Holosun this morning so we'll see how the warranty claim goes. Leupold warranty is like 6-8 weeks last I had to send one in - but that was over a year ago. I've never had to warranty my trijicons.
The robustness of the RMR is significantly more than pretty much every other dot - it's not indestructible - but it's pretty close. If it fails - it's going to be a failure due to electronics and not the housing/glass. Most of the aluminum ones will fail due to the shroud deforming causing the glass to break.