I use 2 different roaming services, KeepGo and just recently Flexiroam X. They both have data only service that is good for a year from date of purchase. KeepGo charges $99 for 3Gb and Flexiroam $80 with an annual $9.95 plan renewal for 3Gb also. I just left Portugal and got good service from both. Generally 10-15Mbps downloads, with multiple carriers usually available. Both plans Allow for old data balances to carry over to new purchases, so you don't have to "Use It Or Lose It". I used KeepGo in Australia, Bali & Singapore last fall and it worked fine from day one. Check both websites to see all the countries covered and other details that may be pertinent to your needs, but they are an easy way to have trouble free data available in most commonly visited locations.