Yes, we evaluated several other alternatives. Ultimately, we felt that MongoDB's was at the sweet spot of best fit (to our needs) and maturity.

We tried to run Mongo on Windows and that was a bit of a disaster so we are running it on Linux.

Just to clarify it: MongoDB main target platform is Linux, the Windows version is clearly a second-class citizen at this time. Not only the Windows version performs poorly under I/O pressure, it also crashes and leaves the database in a corrupted state (again, this only happens under significant I/O pressure, but it indeed happens).

I've only ever run it on a linux environment, I have not heard great things about the windows version.

Are you guys using Mongos (for running several nodes) or just standalone Mongod?

If Mongos, can you talk a little about your experience in setting that up? If not, can you speak to why you chose to run it in a single node?

Sorry, I forgot to answer that, we are running mongod :)