I only have a climber. This is my first year using a tree stand, and I'd say I use it about 65% of the time. I like being up in a tree for several reasons, but climbers are a PITA on many levels. Since I only hunt public land, they are my only option if I want to get in the air.
I won’t vote since I have never used a lock on or ladder (what’s the big difference?), but I would vote for one or the other over a climber in a heartbeat if I had private land to hunt. I don’t care how good someone has become with a climber, there is no way you are going to be less intrusive with the noise you make or the time it takes you to get up into the tree and settled in, etc than you would be with a stand already in place. The only advantage of a climber is mobility….and possibly comfort with the lounge chairs some come with (like the Summit Viper). Fixed tree stands win in every other way.