update README

Author: gaissmai

README.md

@@ -55,10 +55,7 @@ contain overlapping IP addresses, just in a few nanoseconds.
 There is an example demonstrating how to use bart concurrently with multiple readers and writers.
 Readers can access the table lock-free, while writers synchronize using a mutex to ensure
 that only one writer can modify the table persistent at a time.
-See the test `ExampleTable_concurrent` for a concrete example of this pattern.
-
-The lock-free implementation using the ...Persist() methods is still in an
-early stage and has not been fully tested yet. It is not recommended for production use at this time.
+See the `ExampleTable_concurrent` test for a concrete example of this pattern.
 
 A `bart.Lite` wrapper is also included, this is ideal for simple IP
 ACLs (access-control-lists) with plain true/false results and no payload.