From what I've read and had some YouTubers say attachments work differently on different guns.
For me on AR'S quickdraw is a must.I typically also use grip as it actually works on most guns now. SMGS is quick draw, laser sight,fast mags or extended mags. Long barrel also works well on them.
Really it's all up to you. I use either no sights or a red dot. Hate acog as they bounce to much.