One myth that needs dispelling: In grapes, unlike fruit trees, older/larger vines do NOT gain you any time in getting them into bearing. What counts is that the vines are healthy and have at least two or more large (1/8 to 1/4 inch diameter) roots. The roots don't even need to be that long. If they are cut or broken to three or four inches that is still enough. Why? Because any transplanted vine needs a full season to re-establish it's root system, and even short roots are enough to allow the plant to re-grow roots quickly. That's the first year. The second year the vines are cut back to two buds and a new shoot is trained up as the new vine's trunk. The year after THAT, the vine can start having crop.

Odd as it sounds, if you get roots started on a cutting, set it in it's final location, and give it good care, you can train the new growth up the same season and often get some crop the second year, a year sooner than with rooted vines.

The big advantage with planting rooted vines is that they can take more abuse than a newly rooted cutting. But give a newly rooted cutting good care and it will give you crop the next season. I've personally produce a vine nine feet long from a cutting in one season. Got it to the top of an arbor and had a nice little crop the next year.

You can't do THAT with fruit trees.
-Lon Rombough