Best Tour Company

I have been very happy with everything we've done with Walks of Italy, BUT their Pompeii tour is really expensive. You could do it on your own for less, even if you hire Gaetano Manfredi, who is THE BEST and most expensive guide there. But if you hire him you will NOT regret it!

I booked 3 tours thru Verizon which uses Viator. The Verizon reward points can be redeemed for Travel activities - knocks 10-20% off of the normal Viator cost:

1) 3 1/2 hr bike and food tour around Rome. Very enjoyable and informative tour. Only 6 of us in the tour group - us and 2 others. Ear pieces were provided which enabled us to hear everything our guide said even if you were 20-30 yds away from him. Highly recommend.

2) Walking tour of Colosseum and Roman Forum. This was a much larger group - 18 people. The larger group, no ear pieces and heavy Italian accent made it difficult to hear/understand. Recommend you try to get a small group tour.

3) 1 hr Running tour thru Florence. I know you are asking about Rome but this 3rd Viator experience was also very good. It turned out to be just me and the tour guide - literature said up to 6 people. He was extremely knowledgeable and informative - and unfortunately a very fast runner :-). Really enjoyed it.

I thought Viator was a consolidated or reseller of tours and not a tour company. We were very pleased with Walks of Italy in Florence and Angel Tours in Rome.

Used Walks Of Italy for all our tours last year in Venice, Florence, Rome and Vatican. Very pleased.
They did a great job. Only one of our tours had 12 people. The rest, 8 or less including my DH and myself

We used Walks of Italy in Rome and Venice. Outstanding! We took the driving tour of Rome! It was our favorite. The tour of the Colosseum Underground and third floor was well worth it! We took the boat tour of Venice. It was amazing! We were the only 2 on the tour! We didn't take their tour in Florence because they didn't give tours that day. In Florence we booked through Atviva. Their tours were also very good. Another thing we did in Rome was a food tour, Eating Italy. here
We really enjoyed the food tour. We took the evening tour through Trastevere. Highly recommended.

We have done the Pristine Sistine tour wiht Walks of Italy and a private "Antica Roma" tour with Context Tours. We preferred the Context tour as it was more personalized --- but it was private, so of course it was!
I think that all of the major tour companies to an excellent job. My husband and I traveled extensively, usually in the fall and never needing a "tour." But we are traveling in high season now with our kids. The tours have been ESSENTIAL and worth every penny.
We had a private guide for the Ancient sites - colosseum, furum, Palentine Hill. Context tour was just great and we all learned so much.
We did the Pristine Sistine from Walks of Italy. Do NOT bother with the Vatican in the summer months without a tour guide. I can't believe I am saying this, but it was insane. Everyone knew our guide and we managed to at least see highlights in three hours. My husband and I were here in 1999 and had the Vatican to ourselves by visiting at off hours during "shoulder" season. This year, in summer, we entered as early as possible (we were the second tour group in the special line with Walks of Italy). We had relative peace in the Sistine Chapel (just fabulous) but the rest of the museum was intense.
St. Peter's was comical. We could not get anywhere close to the Pieta. My girls only will remember the crazy tourists with their selfie sticks there. We actually went BACK on our own at 7pm (30 minutes before closing) and it was still so jammed we could not get close to the Pieta. It makes me sad since this is the most perfect statue I have ever seen (I reacted very strongly to this piece when I saw it 20 years ago) and I wanted to share it with my girls. I guess Iwill have to find a time to come back in "off season" for them to see it.