I downrig alot after spring. I have used Scotty and I now have Big Jon downriggers. I prefer a vertically mounted spool if you are going to purchase manual (hand crank) models as opposed to a horizontal spool. The horizontal spool like what the Scotty's have is just ergonomically uncorfortable. The Big Jon's are 90% aluminum, very little plasctic. They are about the toughest I've seen. They are a little more money but I think well worth it. I've also found if you can mount hand crank models a little higher off the gunwales it is alot easier on your back, so your not hunched over cranking all day!
The biggest challenge in the downrigger learning curve is the realease. I have used probably every release sold by Cabelas, even releases designed by salt water companies. I now use the Cannon pinch-pad releases exclusively. The key is to have a release that holds the line while you descend your weight, but will release the line upon a solid take by the fish. I don't live by the rule that the line MUST be released upon hookup, but you do want the line to come free with a sharp quick UPWARD motion of your trolling rod. Most people who fish in my boat want to pull the rod foward to the front of the boat to pull the line free from the realease. That only pulls the line through the release not out of the release. I also recommend using only braid or fireline as your line.
I've used just about every type of bait while downriging. While downriging for Lakers, I consistently will outfish other boats 5 to 1 with my setup. First, find what the fish want that day, spoon, stick bait, jointed rap, artificial squid bait, etc... Then find if they like a certain color better, although I think color is only 20% of the type of bait the fish are in the mood for. I will give up one secret for Lakers, when nothing seems to work, put on a Kokanee setup. I downrig when the fish require me to exceed 40 feet deep. Above that I troll lead line. I've never liked three way rigging with heavy weight, but that is the cheepest way to get deep! Good luck.