We used RomeInLimo also. They were wonderful.
For our Med cruise, we used RIL for the Italian ports and used up some OBC for the Nice/Monaco tour through
DCL. It wasn't a bad time at all but it's hard to herd 30 people on a bus with several stops. At the Monte Carlo stop, we lost 2 people in our group. After waiting over 30 minutes for them sitting in a hot bus with some whining small children, we finally left. I often wonder what happened to them, if they were sick, injured, or just lost track of time while gambling.
Anyway, it was good that this was our first port and the whole time we knew that the rest of the cruise we had private tours. A group can only move along as fast as the slowest one in the group. If that's not someone in your family, it can get annoying because he/she is slowing you down. If it's a member of your family, you're more likely to notice that he/she is constantly struggling to keep up with the group, arriving last at each new area sometimes short of breath, sometimes missing the beginning of the guides next topic, feeling so exhausted and just not having a fun time.
Having a private tour eliminates all of that stress .
Personally, I'd reschedule the cruise if we were forced to book excursions through DCL. We are a family of 4 and split the RIL cost (3 ports) with my parents. We got a discount for booking more than one port tour with them and also another 5% off for prepaying in cash (wired).
It came to around $1800 which we split so $900 per couple. DCL excursions were approx $500/pp/port. That would be around $2000 for my family for each Italian port, or $6000 total for Italy. NFW.
Hmmm... $6000 to be herded onto a bus vs. $900 for a private Mercedes with WIFI hotspot? This is a no brainer.