My girlfriend and I did the self-guided tour. This was our first bike tour, and we both had an amazing time. The first 3 days were primarily on cycle paths while the last 2 days were mostly on country rides. Do be mindful that the last 2 days are slightly hillier while also having to navigate some traffic. Biking in to and out of Verona was slightly difficult due to the car traffic.
The experience with the contracted tour company was very efficient and organized. Our luggage were always in the next hotel by the time we arrived. The bikes were sturdy. The directions were accurate (we downloaded the GPS tracks to our phone). The hotels were all very clean, private, and most importantly had very warm showers.
Our favorite part of the tour was the city of Bolzano. It is unlike other cities in Italy, partly due to its German/Austrian influence. Take time to explore the city and also take the cable car up to Ritten and do some hiking prior to the start of the bike tour. The scenery is ridiculously beautiful.