Cell Phone While Visiting the US

Every time I visit the US I take a POS basic Verizon PAYG phone with me. Every time I have to spend the first one hour of my trip getting my account set back up again because they recycled my number due to lack of use (one visit to the US per year).  Also no data on this old phone. I'm tired of it.

I wonder if there are flaws in my new line of thinking:

1. I have a Vonage box here in the UK with a US number (520 area code). I use this for work making calls back to the US. Also friends/family in the 520 area can call us for free.

2. I can get a Three PAYG "All-in-one 20" SIM for one month for £20. This includes calls, texts and data.

3. With Three's Feel-at-home roaming to the US doesn't cost any extra - it just comes out of the allowance, although data is capped at 12GB/month, which is plenty. Calling a US number is 13.8p/min.

4. On Three's roaming receiving calls from any number is free (http://www.three.co.uk/Support/Roaming_and_international/Mobile_Roaming?content_aid=1214306357859).

5. On Vonage I can forward my US number to my UK cell phone number.

6. I asked Vonage and they told me, with the forwarding in place, anyone calling me from the 520 area doesn't pay for the call because they are calling my 520 number. Instead I pay 34c/min for the forwarded call, and it is simply added on to my monthly Vonage bill.

Seems straightforward - I pay for receiving and making US calls and I get 12GB of data. US friends and family don't pay anything, which is perfect.

What is the catch?

After years of messing about with 'cheap' PAYG US-based phones, and wasting time and $$, and because I don't actually use my cell all that much anyway, I decided on a PAYG with 3. On the last trip, it was great. Called DH, he called me, no problems.

As I am retired, I don't have a work issue, and my father's land line sufficed for local calls.

I recommend 3 for the calls to the UK part. Actually, I've been much happier with coverage etc. with 3 over O2. I get a signal when some other family members on other carriers don't. Definitely worked for me.

I've used Vonage back when I worked, and the call forwarding sounds like a decent way to go. Alternatively, just get a cheap disposable (Net10 or similar) on the cheapest sim available, and give non-business contacts the *new* number.

I keep an Oder phone for use in the US, and have an H2O sim that I top up with $10 every 90 days. The only thing I have to do when I turn on the phone is download the apn data settings- for some reason these disappear when the phone has been switched off. This works for me as I keep the same US number, and it's relatively easy to top up via Skype using H2O's automated system and my US bank acct debit card. Calls cost 5c per min, texts 5c, and using data for iMessage is cost effective. Using data to check email and Internet is quite expensive but I mostly use wireless. Works for me, might be a good recommendation for anyone who travels to the US a couple of times a year and likes the convenience of having the same number.
https://www.h2owirelessnow.com