I have also been looking at getting a new orange phone on their tarriff match (Orange Value Promise) scheme, but what I am finding is that if you connect to one of these plans rather than their own "your plan" things, you won't get a free/cheap phone, you will have to pay full whack, and I suspect with the SPV that will be a fair bit!
Also, Orange do monthly text messages bundles, but NOT if you are on a matched tariff, and the Orange Care insurance package will cost you an extra £5 a month if you want it.
If you aren't determined to get the SPV you could go on the T-mobile tariff called "everyone 200 off-peak" which is around £15 a month, and includes 200 off-peak cross-network mins, tho no texts. However, you could get text messages bundles seperately and it still works out less than the orange 120 deal!
Hope this helps...