When comparing ripgrep vs vimgrep, the Slant community recommends ripgrep for most people. In the question“What are the best open source tools for searching source code?” ripgrep is ranked 2nd while vimgrep is ranked 5th. The most important reason people chose ripgrep is:
ripgrep has performance similar to raw grep but provides similar level of usability as The Silver Searcher or ACK.
Specs
Ranked in these QuestionsQuestion Ranking
Pros

Pro Fast
ripgrep has performance similar to raw grep but provides similar level of usability as The Silver Searcher or ACK.

Pro Supports VCS ignore files
ripgrep can speed up by ignoring files matched by pattern in ".rgignore" (deprecated), ".ignore" (since rg-v0.2.0), and VCS ignore files (e.g., currently only ".gitignore").

Pro Speedy even with Unicode (UTF-8) searches

Pro Lock-free parallel recursive directory search
Pro ripgrep lets you only search certain types of files via file type whitelist
Pro Supports extented regular expressions
Using the \v string at the start of the pattern enables magic (extended regular expressions)
Pro Built in to Vim
You don't need to install any plugins to use vimgrep, it comes built in to vim.
Cons

Con Does not support encodings other than UTF-8
If you need to search files with text encodings other than UTF-8 (like UTF-16), then ripgrep won’t work. ripgrep will still work on ASCII compatible encodings like latin1 or otherwise partially valid UTF-8. ripgrep may grow support for additional text encodings over time.

Con Does not support decompression
If you need to search compressed files, ripgrep doesn’t try to do any decompression before searching.

Con Does not support arbitrary lookahead/lookbehind assertions
However, it's supported since ripgrep v0.10.0 (2018-09-07)
https://github.com/BurntSushi/ripgrep/blob/master/CHANGELOG.md#0100-2018-09-07

Con Does not support backreferences
However, it's supported since ripgrep v0.10.0 (2018-09-07)
https://github.com/BurntSushi/ripgrep/blob/master/CHANGELOG.md#0100-2018-09-07
Con Slower than external grep solutions
External grep programs can be much faster
