When comparing Microsoft SQL Server Management Studio (SSMS) vs A5:SQL Mk-2, the Slant community recommends Microsoft SQL Server Management Studio (SSMS) for most people. In the question“What are the best SQL Clients for Windows?” Microsoft SQL Server Management Studio (SSMS) is ranked 9th while A5:SQL Mk-2 is ranked 16th.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Can work for other databases if Linked Servers are used
Pro Great for SQL Server
Pro ER diagrams
Supports two-way Entity Relationship diagrams.
Pro Excel support
Support for Excel input and output.
Pro Portable
Can be made portable by simply creating a folder "Portable" in the app folder.
Cons
Con Bloated
SSMS eats up a lot of disk space and memory, but Microsoft seems to have addressed the issue in the newest version, quote "The current size of the bundle is less than half of what SSMS 17.x is (~400 MB). The size will eventually grow a little when the IS components are added back to SSMS, but it should not be as large as it used to be."
https://docs.microsoft.com/en-us/sql/ssms/sql-server-management-studio-changelog-ssms?view=sql-server-2017
Con Doesn't natively support other databases
SSMS is aimed at SQL Server.
Use of Linked Servers will give you some access to query other types of DBs using the tool, but this is a workaround.
Con Website
The website is mostly in Japanese.