Along with doing the math to see if passes are of economic benefit, do be aware that they don't allow you just to stroll into every attraction they cover. Some of the most-visited of them mandate advance, timed-entry reservations, even with the pass.
You also have to have enough time and interest in the attractions covered to see enough of them to justify the cost of the pass, and do that at less than a dead run.
I've personally never been a fan of the Roma Pass as the 72-hour version (I wouldn't even think about the 48-hour one) only fully covers entry to 2 attractions. The 2 that pass is most commonly used for are probably the Colosseum and Galleria Borghese. Both of them require advance, timed-entry reservations. While it covers use of public transport (excluding to/from the airports) Rome's historic center is a walking experience so we've used their transport system only a couple of times over a couple of trips. If needed, just buy a couple of individual tickets for 1.5 euro a pop. That pass also doesn't cover anything at the Vatican. See the FAQs for the fine print:
https://www.romapass.it/en/FAQ/
The Firenzecard was just recently brought back to life again, and I feel a little more positive about that one IF you have a solid 72 hours to use it, and IF you want to see enough of what it covers. It's an even better deal if you have enough time to use the free, additional 48-hour restart. Yes, a couple of those attractions, such as the Uffizi, require advance reservations but entry fees to many more attractions are FULLY covered compared to the measly couple under the Roma Pass. It doesn't cover any of the duomo complex structures (bell tower, dome, baptistry, museum) so that would be a separate purchase. As well, it doesn't cover any public transport but Florence's historic center is even more compact than Rome's so no need for it, IMHO. Again, see the FAQs for details:
https://www.firenzecard.it/en/faq
Combo passes for the duomo:
https://operaduomofirenze.skiperformance.com/en/store#/en/buy
We'd used a different pass for our 5 days in Florence that has since changed enough that I wouldn't buy it again unless having the time for multiple trips to the Uffizi, and am confident we could probably break even on a Firenzecard with advance planning, even without the restart, and you don't have to have advance reservations for quite a number of the attractions covered. YMMV.
