Questions about electrolytic capacitors

Hi, I would like to learn some things about electrolytic caps.
I have to recap some preamps and replace these caps:

Samhwa 470uf/16v (SG) 85deg. (M) 8803

SMZ 47uf/63V (M) 85deg. 2(k) 5H

Elgen 470uf/10V M -40+85deg. VENT

What's the meaning of: (SG), (M), 2(k), 5H and VENT?
Why there's different brands used? Should I replace them with different brands as well?
Thanks!!

Generally speaking, it i better to replace them with 105°C caps.

Samhwa are fine lytics.

If you're recaping also the PSU, low ESR caps wouldn't harm either.

I don't know what all those letters mean specifically, but they are likely the manufacturer's type code.  For example, common Panasonic caps that folks like to use are FM and FC series.  You can replace them all with the same brand and temperature rating (I agree that 105 degree is better) as long as the value and voltage are the same or higher.  For example, you could order two 470uf/16v instead of one 16v and one 10v.