Duncan,
I keep the buggers waiting for their money by paying in bits and grabs, aka, monthly Direct Debit. This has the additional advantage of preventing the scumbags succeeding with what they've tried on with you. I appreciate that you may not want TV licencing to get direct access to your bank a/c but all DD users have to sign up to a code of practice making them behave.
In general, attempts to speed up your decision making are done with the aim getting YOU to do what THEY want. This applies just as much to genuine companies who use expressions like, "hurry, sale ends on Sunday", as to the scammers who want you to push go/yes before you've had time to think and study their fake website in close detail. Like Spencer Davis, I keep on running, changing passwords, email a/cs, passcodes and anything else that allows me to ring the changes. So far, so good!
John