I have used leaders at times and at other times not. At the moment using an Alvey Im using a swivel so I always use a leader. My Penn 4500 Spinfisher has 14lb superline to a 30lb leader. I found a good knot for braid to mono, or mono to mono different sizes, Its called the Stren Knot and is as easy to tie as any. Start by joining the leader and main line by tying a uni in the leader. Then tie a 11 wrap improved clinch in the thinner diameter line, pulling them together. I dont know how to post a link but search Stren Knot.
The Stren Knot didnt help today when I got smoked by a suspected Mac tuna. I had 9lb onto 15lb leader trolling a lure. Got smoked a couple of hundred metres(no hope of stopping it) in no time flat untill I applied a bit to much pressure to the Alvey and the mainline broke. I have never seen the little Alvey spin so hard untill it was SMOKIN.
The Stren Knot didnt help today when I got smoked by a suspected Mac tuna. I had 9lb onto 15lb leader trolling a lure. Got smoked a couple of hundred metres(no hope of stopping it) in no time flat untill I applied a bit to much pressure to the Alvey and the mainline broke. I have never seen the little Alvey spin so hard untill it was SMOKIN.