[m419]

Yes it would but O2 Unlimited would still be in the league because there is no subscription fee and there are no limits to the number of O2 phones you can call and whatsmore, standard call charges are in place for non-inclusive calls.

How unlimited calling bundles compete:

O2 unlimited:

Unlimited Calls and texts to O2: Free (Providing you topped up with £15)
Unlimited texts to O2: Free (providing you topped up with £10)
Calls to other UK networks: 25p per minute
Calls to UK landlines: 25p per minute. After 3 mins of calls,5p per min
Texts to UK landlines/other networks: 10p
Minimum call charge: 10p
Voicemail: 10p or free if you have O2 unlimited calls,to access voicemail free, dial your own o2 number from your mobile on private number and press * and enter voicemail pin

T-Mobile 5 Day pass:

Unlimited calls and texts to T-Mobile phones for 5 days: £7.50
Calls to other UK networks: 25p per minute (15p on Everyone)
Texts to other networks: 10p (3p on Text appeal)
Picture messages: 20p per message
Voicemail: 10p per minute (Free on Relax payg) Or if you have the 5 day pass just call your own mobile number.

Vodafone Family on the Anynet plan

£5: Nominate and call 3 Vodafone numbers for unlimited call between numbers for a month.
Calls to all networks and landlines: 30p per minute daytime, 5p per minute at evenings and weekends.
Texts to all networks: 12p per message
Picture messages: 36p per message

So the cheapest out of the 3 is the O2 Unlimited offer as once you've topped up £15 you have unlimited calls and texts to other O2 numbers and you can spend the £15 credit for other services such as calling other networks and buying O2 bolt ons including O2 web and wifi.