I have not taken a tour with Roberto Becchi. But over the last couple years, I feel as though I've gotten to know him, "virtually', and I like the way he thinks/feels about his region. He has a home just outside Siena where he rents cottages, makes wine and olive oil and runs his tour company. You can become "acquainted" with Roberto by watching, "Tuscany Beyond Expectations" on Amazon, or by looking at the Guide Collective (created by RS former guide, Sarah Murdoch) website/facebook page.
And anyone that enjoys beautiful scenery, and cinemaphotography should watch "Tuscany Beyond Expectations", produced by Brian Gendece and Roberto. It's stunning.
There is another guide based in Siena that RS et. al., recommend, Anna Piperato.