A number of fishing rods you can buy have models that are 2 piece and models that are 1 piece. I have heard people say their rods snapped in half when they were 2 piece. However, it would be extremely beneficial as far as portability to have 2 piece. What are the pros/cons of each? Would one be better than the other? Since this may be brand specific, I am thinking mostly about Shakespeare Ugly Stik models, but any general information would help!
I fish for everything from 9" brook trout to 15 lb. bluefish to 40 lb. striped bass on both fly rod and spinning tackle, and honestly I don't think I would say that one is better than the other except for the fact that with 1 piece rods you don't worry about losing your tip, OR that with multi-piece rods you can cart them around more easily (and reduce the risk of slamming the tip in a door or something.)
Nowadays the difference between the two is getting almost too little to talk about. Some will argue that a 1-piece is more sensitive, casts better, and is stronger. One thing for sure is that a 1-piece will never separate when casting or fighting fish - something that happens more than you would think due to people not checking the connection in their two piece rods.
That said, most fly rods are multi-sectional. Since they depend on their flex to fight fish and their strength to cast line, it could be argued that having multiple sections is a non-issue. Modern ferrules and lines do a great job preserving sensitivity.
I believe that only Lamiglas is making 1-piece surf casting rods larger than 10'. From what my tackle shop says, a change in shipping rates made it too costly to ship anything longer. So everyone else is making two piece rods for anything longer than 10'.
I have both one piece and two piece. I mostly fish a 1-piece simply for the fact that I never have to pack them and I won't have to worry about the tip flying off after a cast. BUT, if packing size plays any part in the decision, I don't hesitate to take a multi-piece rod.
If you are looking at two piece rods because of their more compact size, you may also want to consider telescoping rods.
I've had (3) telescoping rods & all but the Amazon-special-carbon-fiber job have served me well (the no-name brand amazon one broke into many pieces...), but I've loved the Mako Calypso 8' rod & my much smaller Shakespeare telescoper as well.
With these rods too, some people will try to argue that they lack sensitivity, but I've felt the hits on these & landed anything from trout, perch, & crappie to a stripper off an ocean pier.
Personally, I started experimenting with telescoping rods so I could more easily take them with me while backpacking & biking. Now, they are all I have!
I have used two piece & one piece rods in the past, but that was so long ago I don't think I'd have any practical advice on what is out there now. I'd only note that as @That Idiot noted, multi piece rods do have a tendency to fly apart while casting or fighting a fish IF you don't check the connection between casts. (Note that this doesn't happen with telescoping rods).
I have a lot of 2 pieces, one 4 piece, and 1 one piece. The one piece is my go to rod because I fish at night often (I live 3 blocks away from the Sacramento River). I'll have a tendency of not paying much attention of how my guides are aligned and end up casting to the extreme left or right initially. I never have to worry about that with my one piece rod and I have a truck so portability isn't issue. As for sensitivity, I don't rely on the rod exclusively because of ever changing circumstances like current, wind, etc., in fact I don't hold my rod constantly, I use a bell most of the time.
So it all really boils down to is space and convenience. If you have limited space, then 2 piece is a better choice, if not, then go one piece because in any type of system, whether it be a computer, car, or rod and reel; the less components the better.