Moving data from Microsoft SQL Server to Wave:  Middleware vs. Custom?

Anyone have insights/experiences/links they can share?

We're exploring pros/cons and any insights contrasting different middleware options and approaches.

Our current assumptions:

• Middleware
  • Faster/easier to configure
  • More future proof
  • "You get what you pay for"
• Custom
  • Takes a while to build
  • Harder to maintain/add new functionality
  • May break from time to time with new releases

Any major differences we are overlooking?