I use a sliding back and a 15x loupe to focus, and, for interiors, add in checking the focus on a laptop. For exteriors, I just rely on the loupe and sliding back.
So far so good, but it does take some time to get use to focusing on ground glass. (I know others have had problems with their sensors not lining up exactly with the ground glass, but mine is pretty much spot on.) Also, checking the focus on the edge of the frame is not possible with just the sliding back since you can not get the loupe that close to the edge without hitting the housing.
With the wides, you will find the DoF is so good, that it does not matter as much if you do not hit the focus perfect. As long as you are close, everything will be tack sharp anyway. And after a while, you will get to know your lenses and where the focus will be based on the numbers, and will be able to adjust accordingly without really thinking about it.
The only lens that I am extra careful with is my 90mm, due to a smaller DoF. After some practice though, focusing on the ground glass works great for me.
I know some are against getting the sliding back due to more stuff to carry around, and looking at the image upside down and backwards and other reasons that I can not remember. However, I find it to be a real benefit; it is much easier composing an one-point with a sliding back than using live view or that viewfinder thing.