What is most valuable?
The memory footprint is the smallest in its category of products. I think Microsoft did a very good job squeezing as many features as possible in such a tiny executable. The price, being it free, it's of course a plus. And the capability to do almost everything as in the commercial version. When using a developer machine or also a virtual machine, it is essential that every MB of memory is well utilized. The binaries are loaded in memory only when needed. It uses the same client libraries as its bigger siblings, including the Native client. Unlike the Compact version which uses a limited set of functionality this LocalDB has Stored Procedures, Geometry, Geography data types, online backup, transactions, data integrity etc. It runs as a separate process as opposed to in-proc DLL.
How has it helped my organization?
For the development process and for small Business Intelligence projects, this software gives a very good head start because the installation is merely seconds. It runs in the current user context, and this allows the developer to be freed from switching accounts many times during the develop/deploy/test phase.
What needs improvement?
The storage limit is about 10GB, so for medium to big databases it is not applicable.
For how long have I used the solution?
I've been using SQL Server since version 7, so approximately 15 years, this 2012 Express is the latest release of this software. This is a free lightweight version of the 2012 full fledged product.
What was my experience with deployment of the solution?
No. The setup is really Next -> Accept ->Next -> Finish.
What do I think about the stability of the solution?
What do I think about the scalability of the solution?
Of course you won't use LocalDB if you need to scale. I mean, in order to scale one should buy the commercial version of SQL Server. But even so, the database will not need any modification. According to Microsoft web site: "Upgrade from SQL Express to paid SQL Server editions is a matter of typing in a license key and no installation is required"
How are customer service and technical support?
I did not use the customer service, the sheer amount of information, articles, blogs and forums about SQL Server covers practically the 99% of issues one may encounter with this database system Technical Support
I'd rate it "good enough", based on previous products experiences.
Which solution did I use previously and why did I switch?
I used both SQL Server and other open source RDBMS. I switched because of the vast knowledge base and the far better feature list in SQL Server.
How was the initial setup?
Very straightforward. One download, pick the 32 or 64 bit version and run the SqlLocalDB.msi installer
What about the implementation team?
In house, literally in "my" house.
What's my experience with pricing, setup cost, and licensing?
Setup cost, 0€. Day to day cost 0€, excluding power consumption.
Which other solutions did I evaluate?
I also used Oracle 11 XE, MySQL, PostgreSQL.
What other advice do I have?
The only caveat is to pay attention to the user context. The SQL engine doesn't run with a privileged or system account, so it really has only the permissions of the currently logged in user (files, network, etc.). It is advisable to install the SQL Server management studio (also free) to administer and configure it