I own half a dozen different mounts, pros and cons to all.
A. Nea railed handguard is OK, make sure it is a fairly tight fit, or it will wobble. Upside is, it holds zero, and can do lower third co-witness with many low sitting optics.
B. Nea barrel attached rail segment. Holds zero, doesn't need to be removed for cleaning, but will mark the barrel when attached, so you better like it. They are disco'd, but can be found on the EE.
C. Nea rear rail/ar stock adapter. Holds zero, doesn't need to be removed for cleaning, puts the optic closer to the eye (which I prefer), but is also disco'd, and hard to find.
D. BC tactical rear sight base. Holds zero, but replaces rear leaf sight. Has to be modified to fit 7.5" vz-58 because of tiny piston.
E. CSA side mount rail system. Holds zero, is easily removed, can be left on when cleaned (rear cover juuuust slips by), allows longer optic, close to the eye, but sits high. Iron sights still visible.
F: Railed top cover. Holds zero, but is a little bulky. Some like this option best, but I find it ruins the guns lines. Fashion/function fight.