XLIFF Machine Translation Support

Hey Guys

I am wondering what platform/services people have used to machine translate and XLIFF (XLF) file that can be successfully imported back into a module (e.g. for RISE). 

It seems like when I use Matecat or Language Weaver, its malforming the XLF file.  The XLF will import back in successfully but no changes are made to the module and it remains in the original language.

I was told by the Articulate Engineers that Smartcat works - but this seems like a surprisingly expensive option considering other options - or SDL Trados Studio -which is likely better for a professional translator to use as its desktop software that needs to be installed.

Has anyone used other services successfully?

Thanks!