I am starting a testing project at work and we have nothing in place.

Should I use a tool like browserstack and try to hold my selenium tests there or bite the bullet and use something like spec flow to write the selenium tests by hand? The advantage being full control, easy way to integrate with CI and easier to integrate to existing workflows (no need for visual studio and a browser open to work on in parallel).

If I do that I will also need some way to do cross browser testing which I guess will require me to export the tests somehow to a cross browser treating service like browserstack.