This has replaced my venerable T-Mobile PAYG with 5 day web n walk pass. The only slight con is that they are still rolling out 4G (although London has just been switched)
For frequent or even infrequent travellers to Blighty, the best Pay As You Go sim by a long shot is the new 321 tariff from Three Mobile. No minimum top up and no expiry, just a simple 3p per min for UK calls, 2p per text and 1p per MB.
How good, or otherwise, is their network?
I was on O2 over the Christmas period and oh my word were things bad while on the move
That sounds interesting. My mifi is locked to Three, I'll take a look at that next time I'm over.
Three have by far the best 3G network in the UK, speeds of >10Mbps are standard. Once 4G is rolled out this should improve further. The major complaint about Three are their customer services, which in a word are diabolical. So in a nutshell, good product but poor support.
Unfortunately the 321 offer is restricted to telephone/smartphones.. not dongles or tablets. I tried in vain to buy one for my cellular iPad and the guy in the store told me that if they spot such a device (presumably from its MAC address) they would immediately block it. So instead I bought their Mobile broadband PAYG data sim (1GB - £10 - 30 day duration). Clearly the 321 offer would be better since you have no expiry and only pay for what you use.
This is on HSPA+. As fast as orange 4G in Switzerland!