The $10/day Verizon plan gives us the same service as our domestic plan. In our case, we get unlimited calling and texting and 8G of data each month. Unused data rolls over for future use.
There is another Verizon option. It's $40/month but instead of using your allotment you get 100M of data, 100 minutes of calling, unlimited incoming texts, and some number of outgoing (100?). Start date is whenever you pick (we were actually gone for 31 days so we had one phone start on day 1 and one on day 2 so we wouldn't be without or pay for a second month). Go over these amounts and it's pay as you go, including $25/100M of data. Probably should double check these numbers since I'm pulling them out of my memory from a couple of months ago.
We just went to Europe for a month. Felt that up to $600 for the two of us seemed like a lot of money. We have a low level of data on our plan, rely on Wifi and aren't heavy data users, shoot, not heavy phone users. We turned off all the data updates, e-mail, application updates, etc. Then only did those things on Wifi. We would selectively turn on data for something particular if needed when out and about. I wanted to be able to get incoming texts related to credit card usage (we recently had one of our card numbers stolen, didn't want one getting suspended on us over there).
Neither of us could stay under the 100M of data, though my wife was close and I think except for one oops related to instagram she'd have made it. Particularly wanted to be able to use it for maps and finding our way around. Note that you can get on google maps once in a new location to get the map updated (either wifi or cell), and then turn it off. But the GPS keeps working, so you aren't using data.
I will say that about 50M of data each was going to "system" functions that we couldn't turn off. So at the end of the month we had them always available, but sparsely used on cell data, and did it for $130 for 2 phones.
On a semi-related note... two of our weeks were on a ship going from England to Russia and back, think it was 8 times we changed time zones by an hour. The ship had... "ship time" which didn't always agree with the actual time zone. While most times our phone picked up GPS and updated to the actual time zone, once it didn't until we arrived. Keep this in mind when using your phone alarm in the morning if you need to get up! And keep a second time (we used our kindles which are manually set). First time this happened we were getting up and weren't sure if our phone had changed or not.