Roam is fine for the US (I think they are in MX now too?).
For Europe I bought a WorldSim card years ago. It was good at the time when it was more difficult to get a local SIM card in Europe. Now though, the price point just isn't there. I find them and any equivalent insanely expensive for data.
For example, I was just in France and Italy and I bought an Orange SIM in Paris. I got the "holiday" package which gave me a bunch of minutes and text plus 1gb of data for a month anywhere in the euro zone for 40€. I used up at least 600mb on the two week trip. At 0.3 cents/100kb through WorldSim I'd have spent many times more that 40€. There are cheaper options in Europe from discount carriers like Lebara but they are akin to using Wind whereas Orange or the other real carriers give you full on LTE. I bought a Lebara SIM the previous year in Paris and I wasn't thrilled with the internet speed. It would do if you don't care. The Orange card is a good deal of you're hitting up multiple countries.
The only good thing about WorldSim or the equivalent is they don't cancel your SIM after a certain time of inactivity. With a local SIM you need to keep topping up in order to keep it. With Roam you need to pay for a day of usage and then the SIM stays active for I believe a year. If you use it even every couple of years it's worth it vs the cost of buying a new SIM.
__________________
|