docs(migrate9): update for release

Author: hasezoey

docs/guides/migration/migrate9.md

@@ -6,7 +6,7 @@ title: 'Migrate to version 9.0.0'
 Here are the Important changes made for 9.0.0
 
 :::caution Important, Read this first
-This Guide is written for migration from version `8.15.0` to `9.0.0`, for versions `>9.0.0 <10.0.0`, please consult the [CHANGELOG](https://github.com/nodkz/mongodb-memory-server/blob/master/CHANGELOG.md)
+This Guide is written for migration from version `8.16.0` to `9.0.0`, for versions `>9.0.0 <10.0.0`, please consult the [CHANGELOG](https://github.com/nodkz/mongodb-memory-server/blob/master/CHANGELOG.md)
 :::
 
 ## Breaking Changes
@@ -17,11 +17,15 @@ With 9.0.0 the minimal nodejs required is `14.20.1`.
 
 ### Mongodb Driver Version upgraded to 5.x
 
-The used MongoDB Driver version is now `5.6.0`.
+The used MongoDB Driver version is now `5.9.0`.
+
+### Default binary version is now 6.x
+
+The default binary version has been upgraded from `5.0.x` to `6.0.x`. For more specifics see [mongodb-server-versions](../mongodb-server-versions.md).
 
 ### Removed platform translations
 
-Some platform translations have been removed, because they are either not needed anymore or werent supported in the first place:
+Some platform translations have been removed, because they are either not needed anymore or werent properly supported in the first place:
 
 - `sunos` -> `linux`
 - `elementary OS` -> `linux`
@@ -34,7 +38,7 @@ Some architectures were removed because they were not being build by mongodb any
 
 ### MongoMemoryServer `instance.auth` option is now ignored
 
-With 9.0.0 the option `instance.auth` option is going to be ignored, because its set via the `auth` option directly.
+With 9.0.0 the option `instance.auth` option is going to be ignored, because its set via the (top-level) `auth` option directly.
 
 Example:
 
@@ -50,16 +54,16 @@ Replace `auth: { disable: false }` with `auth: { enable: true }`.
 
 ### MongoMemoryServer and MongoReplSet `.cleanup(boolean)` and `.stop(boolean)` have been removed
 
-Previously `boolean` was the only option for the `.cleanup` and `.stop` function, but they behaved differently between those 2 function and were replaced with `Cleanup` options and now have been completely removed.
+Previously `boolean` was the only option for the `.cleanup` and `.stop` function, but they behaved differently between those 2 function and were replaced with `Cleanup` object-options and now have been completely removed.
 
 Replace `.stop(true)` with `.stop({ doCleanup: true })`.  
 Replace `.cleanup(true)` with `.stop({ doCleanup: true, force: true })`.  
 
-Default is still for both `{ doCleanup: true }`.
+Default is still for both `{ doCleanup: true, force: false }`.
 
 ### `MD5_CHECK` is now enabled by default
 
-The config option [`MD5_CHECK`](../../api/config-options.md#md5_check) has been enabled by default now, resulting in always comparing the downloaded archive with a md5.
+The config option [`MD5_CHECK`](../../api/config-options.md#md5_check) has been enabled by default now, resulting in always comparing the downloaded archive with a md5 after a download.
 
 ### Merged Error types
 
@@ -104,7 +108,7 @@ The Mongodb Binary childprocess is now also `.unref()`, like the killer process
 
 This *should* help with non-closed instances not exiting the nodejs process.
 
-## The port testing has been replaced
+## The port testing package has been replaced
 
 Previously MMS used `get-port`, but it caused some big memory-leakage across big projects, so it has been replaced with one that uses less maps.
 
@@ -115,4 +119,13 @@ It also has been replaced because newer versions were ESM only, but we couldnt s
 Mongob version `7.0.0` removed storage engine `ephemeralForTest`, with mongodb-memory-server 9.0.0 storage engine `wiredTiger` is the default for binary versions `7.0.0` and higher.
 Older versions (before `7.0.0`) will still continue to use `ephemeralForTest` by default.
 
+:::info
+The version used for the decision is the version provided via the resolved [`VERSION`](../../api/config-options.md#version) config option.  
+This mean it needs to match the version the system binary is (a warning is printed if they are not the same).
+
+If the option is unset, the default version will be used, which is likely not correct for the system binary.
+
+If the decision should not be automatic, the storage engine can be explicitly defined as a instance option.
+:::
+
 It is recommended to run those instances with a db path which is equivalent to [`tmpfs`](https://wiki.archlinux.org/title/tmpfs).