Comparing Price Plans

Hi,

I'm looking to do some work comparing price plans from the various network operators.

There's lots of comparion sites but I don't think they really do this.

I'm just wondering what people think is important.

Setting aside the fact that some people text a lot or others make more calls, what do people think is the general rule of thumb when comparing call minutes to texts? Does a call minute have the same value as two texts?

Also, some operators offer free calls to landlines or free vening and weekend calls? what value is attributable to these - as a general rule?

If I've got 1000 cross-network minutes - do I care that I get free evening and weekend calls?

Thanks.