I've used braid for my main line in all salt and freshwater applications for 20 years. With 2%-4% stretch, it can't be beat for detecting strikes, and for that reason alone gets the nod. It's also thin for its strength, so it casts a long way, too. BTW, Braid doesn't abrade guides. (That was the original wonderline, Kevlar, in the 1970s . . . now found in ballistic vests and not tackle shops.)
On the downside:
1. You need different knots, both for leaders and to the lure/hook (if that's how you roll). For those who go direct, I suggest folding the line over and doubling the line for regular knots like the clinch. IMO fish see the line (mono or braid) and don't know what it is. What deters them from biting (sometimes) is line drag in the water, not the color of the braid.
I'm a big advocate of tying on a 10' leader (I use Chameleon for salmon and steelhead) for these reasons: (a) puts stretch in your system; (b) easier to tie knots to lures than if going direct with braid; and (c) allows you to leader your fish without fear of line cuts. (Suggestion: wear fingerless gloves when fishing with braid: if you snag up, you can break it by wrapping around your palm and giving it a direct pull.)
To join mono/FC <25lbs to braid, use a 4x Surgeon's Knot. That's an overhand knot with 4 wraps. (Prior to tying the knot, interlink the braid-mono by wrapping one around the other 20 or so times to increase the surface area contact and boost friction.) This knot, cinched very tight, breaks at 85% the actual breaking strength of the weaker line (usually the mono). Trim the tag ends very close, and you can wind it onto the spool and cast fine, even with a baitcaster.
If using heavier leaders than 25lbs, first double the braid with a Bimini twist (second best: spider hitch) and join the leader using a "Reverse Albright" (Aussie-speak) or an "Alberto's knot" (Google it). A very strong join IF tightened up as hard as you can pull.
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I have more details on braid knots I can share. PM me if interested.