Where Text Replacements stops being enough
Plain text only. A signature with a bold name and a link comes out as characters. Anything with formatting, or an image, is outside what the feature stores.
It fires as you type. Expansion happens on the trigger, which means it also happens when the trigger appears inside a word or in a code snippet you did not want touched. Picking triggers that no real word contains is a habit you have to build.
No folders, no search. The list is flat. At a dozen entries it is fine. At forty canned replies you are scrolling a settings pane trying to remember which abbreviation you invented in March.
Coverage varies. Native apps honour it. Some apps that draw their own text fields quietly do not, and there is no warning when a replacement fails to fire.
The part that decides whether a snippet library gets used is retrieval. Klipto searches snippet body text, not only titles, and across every folder at once, so a half-remembered phrase from the middle of a template surfaces it. That is what you need with a dozen near-identical replies where the titles all start with the same three words.
The heart goes one way on purpose. Liking an item copies it into Favorites and never removes it, so a second press cannot silently delete something you saved last month. To take a snippet out you open Favorites and delete it there with ⌘⌫.
Saving text you paste every day
The other direction is to pick from a list instead of typing a trigger. Nothing watches your keystrokes and nothing expands by accident.
1. Copy the text once, or select the item in the popup with ⌥⌘V.
2. Press ⌥⌘C, or click the heart, and it lands in Favorites.
3. To file it properly, use add-to-folder and put it in "Email templates" or "Addresses". You can make the folder in the same step.
4. Recall it by opening the popup, switching to the Snippets or Favorites tab, and picking the line. It pastes into the app in front.
Folders can be renamed, dragged into the order you actually use, and moved left or right along the tab bar so your main group sits where your eye lands. Deleting anything is ⌘⌫, everywhere in the app. I took out the configurable delete key on purpose, because two different ways to delete the same row is how people delete the wrong row.
The honest limitation
Klipto snippets do not sync. They stay on the Mac where you saved them, which is the same trade as the rest of the app: nothing leaves the machine. If you want the same library on two Macs and an iPhone, Text Replacements gives you that for free, and a dedicated expander such as Snippety or SnippetsLab does it with more structure than Apple offers.
So the split I would suggest: short plain strings in Text Replacements, where iCloud sync is worth more than folders. Longer text, formatted text and anything you need to find by searching its contents in snippets and folders, sitting in the same popup as your clipboard history rather than in a second app.