Thinking about staying in Salerno

Yes, absolutely doable - it's about 45 minutes on the train. And Salerno is a nice town to stay in. It's been a few years since we were there; hopefully someone who has been there more recently will have some accommodation recommendations for you.

Hotel Montestella near station and Concordia dock. Ferries see Travelmar.

Pompei the Trenitalia station [from Salerno] is 2km from the ruins. Pompeii Scavi at the ruins is reached by local trains from Garibaldi, downstairs at NapoliCentrale.

Coming from Salerno on a Trenitalia train, the Piazza Anfiteatro entrance on the east side of the excavation is much closer than the main entrance near the Circumvesuviana Pompei Scavi-Villa dei Misteri station on the southwest side, albeit a little bit longer walk.

To explore trains, use this site:
https://www.trenitalia.com/en.html

Enter "Salerno" in the "From" box
Enter "Pompei" (not Pompei Scavi) in the "To " box,
Choose a date, approx. time and number of passengers.

It's showing 42 minutes between stations at a cost of 2.40 euro PP. Reference a map of the town of Pompei for station location; on google maps it's the FS station south and east of the excavation. From the station, you'd head north on Via Sacra a couple of blocks until it runs out, cut west 1 block to the next street, 2 blocks north to Via Roma, and then west 3 blocks or so to Piazza Anfiteatro and the entrance. It's marked as "Scavi di Pompei Biglietteria" on my map.

On the Trenitalia site, clicking the little i in the grey circle beside the train number will show you the stops it'll make along the way; Scafati looks to be the last station stop before Pompei so that'll be your head's up to gather your things and be ready to disembark at the next stop (Pompei), You'll want to be sure to validate your tickets before boarding your trains to and from Salerno.

We really enjoyed our 2 nights in Salerno this past May
Stayed at Hotel Montestella- very nice newly renovated, about 10 min walk to train and 15 to ferry
Had a wonderful dinner at Mythos
Paestum was lovely, easy train ride

Loved Salerno in 2017. Consider a taxi from the Pompeii station to the Scavi.

It is not right for me to evaluate Salerno, because I've never been there. And I'm the first to say that Sorrento is a purpose-built postwar, reinforced concrete sea resort. It's overrun with sun-seeking Brits and others. But Sorrento has by far the best transit connections for daytripping to Pompeii and anywhere else. And no one will ever ask you, "Hey, what was Salerno like." But many people will ask you about Sorrento. Because of a cruise and a separate independent land trip, I've been to Sorrento twice.

Edit: Because it hasn't been explicitly stated yet in this thread, the Circumvesuviana (Naples-Sorrento) station "Pompeii Scavi" is about 200' from the ticket booth for the Porta Marina entrance to the ancient site. All uses of the word "Pompeii" for 3 Trenitalia stops refer to the modern city of Pompeii.

If we are talking specifically a base for easy access to Pompei, then yes, Sorrento has it over Salerno, difference described upthread. But having stayed multiple nights in both, I'd say that Salerno's charm has it over Sorrento in spades. In Sorrento you don't see the passeggiata, the daily familial late afternoon walk around town that you see in Salerno. Food choices are equal, high quality and reasonably-priced.

The Trenitalia station in Pompei is about a 20 minute walk to the site. You'll be walking all day at Pompeii anyway, so we did not consider this an impediment.

Agree with Tim that Sorrento is a better choice for transportation to some sights. We stayed in both Sorrento and Salerno- liked both very much. If the only sight you intend to visit in the area is Pompeii then Salerno will be fine- also has direct trains to other Italy destinations- unlike Sorrento where you will need the local Circumvesuviana to get you to/from Naples for trains.
Salerno gives you the option of an easy visit to Paestum, ferries to Amalfi, Positano are also easy.
Getting to Capri would be a bit more time and $$. (2 hour ferry with stops in Amalfi and Positano)

We had 9 nights in the area and split our time between Sorrento, Amalfi/Ravello and Salerno. Worked well for our needs.

In Sorrento you don't see the passeggiata, the daily familial late afternoon walk around town that you see in Salerno.<<

The passeggiata in Salerno was delightful!

I've stayed in both Sorrento and Salerno, on separate trips and enjoyed them both. Both are good, it depends a lot on where you want to visit. It's easier to get to Capri and Herculaneum from Sorrento. If you want to concentrate on the AC towns, Salerno is better and you can visit the Greek temples at Paestum. Pompeii and Naples are about the same from both.

We stayed in Salerno this May/June

at: Il Reticolo, SalernoGreat, Via Giovanni Angelo Papio 14, Salerno, 84122, Italy

https://www.hotels.com/ho564980/?display=description

The negative for Pompeii - we entered and exited Pompeii at the Porta Marina gate. It is a moderately long walk to the train station that goes to Salerno.

Salerno was great for walking around.
The brothers that run Il Reticolo recommended a few restaurants.

We stayed there for easy accesses to Paestum - a wonderful day trip - the best day of our trip.

It is also an easy ferry ride to Amalfi or Positano.

Also (off topic) look into the Naples ArteCard
http://www.campaniartecard.it/entra-nel-circuito/

We used it for
* 3 days of public transportation
* free entry to our first two museums / archaeological sites
* 1/2 price to the remainder during that 3 day period

I made life simple for that timeframe.
After those 3 days were over, we just purchased individual tickets, etc.

Thanks to everyone for taking the time to reply to my question. Your feedback will be very helpful in finalizing a few details of our trip, so many options!!