Be careful with the Huawei E583C as it seems to be sold in at least three different frequency configurations:

• UMTS 900/1900/2100
• UMTS 900/2100
• UMTS 1700/2100 (FCC ID QISE583C-52)

A bit offtopic, but there's at least one MiFi type device that covers all five UMTS frequencies (850/900/1700/1900/2100MHz) and that's the Huawei E587u-5. It was available from both Telus in Canada for CDN$150 and T-Mobile in the US for $200. The T-Mobile version was rebranded as a T-Mobile Sonic 4G).

Some dealers still sell it: Buy Unlocked T-Mobile Sonic 4G Mobile HotSpot 4G Router | Huawei UMG587 | E587u-5 | 4GSource.net Wholesale Shop

From discussions I had with a Vodafone Europe rep a few weeks ago, it is unlikely that Toggle will be able to offer the kind of mobile data deals that members on here will be looking for.

Discount voice is not a problem - with data there are a lot of politics and red tape involved.

+Steve :)

Vodafone UK also has a 100MB rate which is not very well published:

• £8 for 100MB in Europe
• £25 for 100MB outside Europe

Vodafone's definition of Europe includes not only the EEA but also closely connected and enclaved countries and territories as well as Croatia and Bosnia.

Thanks. That's a neat device, which I wasn't aware of. I hate Huawei for having such a fragmented product portofolio - at least product names seem to finally indicate those different frequency configurations:
E587u-2 UMTS900/2100
E587u-5 UMTS850/900/1700/1900/2100

Two additional products come to mind
- ATT Prepaid data sim - ATT Prepaids Now Support International Data Roaming Buckets - FlyerTalk Forums
- "Three like home" to utilize one data bucket in Italy, Ireland, Sweden, Denmark, Austria, & Hong Kong.

I recently sailed on a transatlantic from Miami to Rome, stopping in Spain, Italy, & France. Then I spent a layover in Vienna and time in Lisbon. Here's my findings in case you travel to some of these countries.

My strategy:
For voice, I used Piranha and Piranha VOIP when I could find a free wifi signal (usually in a mall).

For data, use wifi and get local sims when I'd have the chance to consume large buckets of data. Otherwise use Vodafone UK sim for data bucket.
Use ship's wifi for crossing from 7-9 pm and after 11 pm when the sky is clear. Most people get on wifi during the day and disconnect during dinner.

Shortest amount of time needed to buy a SIM - possibly 15 min. Longest - Vodafone Spain ~ 1 hr to receive data package activation notice (associate called CS, too, and possibly added some more details to the account). Only place which didn't add the data package without using SIM included credit - Vodafone Spain. They added the credit and purchased the package via the phone. All others added the data bucket to the sim, leaving credit available on SIM.

@Spain
Bought Vodafone Spain for 1.2 GB bucket for < 20 EUR, speeds < 7 Mbps for me. 2G worked a good distance off shore (15 min sailing out from port). No tethering allowed. Clockwork Tether did work. Passport Requested.

@France
Used Vodafone UK 25 GB. I think I saw 2-4 of the major carriers for roaming (Orange, SFR, Bouygues, etc). I think autoselect used Orange for me? Would have expected SFR as a Vodafone partner.
Bought an SFR French sim for family with the prepaid 1 month 300MB data. They said it never connected correctly in Nexus 7 Tablet in Paris. Passport Req.

@Italy
Picked up a TIM Italy sim for 500 GB bucket TIMxSMARTPHONEMAXI. Didn't get > 3 Mbps despite using it in a Verizon iPhone 5 (HSPA+ in Florence). Tether Ok. Passport Req.

@Vienna
Used Vodafone UK 25 GB. Took > 15 minutes to register to a network, longer than what I experienced in France.

@Lisbon
TMN shop couldn't sell me a SIM. FNAC electronic store had Vodafone Pt prepaid sim 1GB bucket for ~15 EUR. It is capped to 1Mbps down but TMN's prepaid bucket was only 250 MB. I still managed to use over 600 MB in 4 days. Tether Ok. No Passport Req.

@Sea
The satellite connection was via OnWaves and my Icelandic prepaid Siminn sim did pick up a voice signal but didn't seem to connect to data. Vodafone UK didn't get a voice or data signal. Vodafone ES might not have gotten a voice or data signal at sea. I believe Italian TIM did roam with voice to OnWaves but it was in the Med. sea and mostly close enough to land.

I also topped up my Vodafone UK sim at WH Smith while on a layover at Heathrow. Also got a data bucket Freebee top up bonus almost instantly after top up.