The full-strength liquid, as it comes to the manufacturers, is very concentrated. This has two potential problems. The first is that one drop of liquid can be over a teaspoon of "sugar-sweetness" -- not good if you want less in your coffee or tea. The other is that the concentrated liquid tends to create crystals in dispensers over time, clogging them up. Different suppliers have dealt with this in different ways.
Here are some forms of liquid sucralose available online and some of the pros and cons of each:
Sweetzfree
Sweetzfree is full-strenth liquid sweetener, with each drop providing the sugar equivalent of about 1½ teaspoons. This is great for recipes requiring a larger amount of sweetener. The smaller size doesn't usually clog. The dispenser on the largest sizes doesn't clog, but drops tend to collect on the outside which crystalize if not removed. Twice in the course of using the largest size I had to remove a "shell" of crystalized sucralose from the applicator. However, this "shell" was handy for sweetening a pitcher of iced tea.