To chime in again, I've used the forward assist, both for a time where I didn't let the bolt slam forward totally on it's own, and so the bolt did not go into battery. Slap the forward assist, and you're live. Similarly, if you check the chamber, you might need to hit the assist. Get one.
As for the dust cover, I have two cats. If I leave the dust cover open, the bolt gets covered in cat hair. Same with dust and such.
IMO, do the rifle right: chrome lined or melonited, chrome lined bolt, dust cover and forward assist.
Springfield Armory M1A 22" barrel in SAGE EBR Mod 0 stock
Dan Wesson CCO | S&W Model 58 blued | S&W Model 29 blued
Springfield 1954 M1 Garand | S&W M&P 15 VTAC 2