Greg
Do your homework! They've definitely improved.
I used Telestial about 4 years ago for a Europe trip and despite a bit of a surprise at incoming costs (low as they were) I thought it was good. Now, there's a lot of different options around, local sims upon arrival are still competitive but riddled with setup issues and limitations on support unless you're in an English speaking country. You need to look into the details on all of these, but Telestial has become even cheaper, support was fine, great reception most areas. Make sure you're more than 1 day prepared and know the details of what you're getting, because compared to the other options I've tried recently, Telestial has no hidden crap whatsoever and is far less of a headache.