? about coil drop springs

[1956cameo]

I was looking thru my parts catalog and saw that they sell 3" drop front coil springs and 5" drop rear coil springs. The coil springs are much cheaper than the 2.5" drop front spindles. However when I look at threads where people have dropped their trucks they always use drop spindles. I was wondering why? Would I run into problems if I used a 3/5 drop on my rig by just using lowered coil springs? Also I want to go as low as I can without having to notch or bag the frame. Is 3/5 too far to go without problems? I have heard some people say it is; and others say it is fine. Whats your take?