It's not just the bandwidth that's a concern for me, it's total usage.
I work from home half the time and can chew through bandwidth quite quickly:-
Broadband connection details:
Downstream 9,235 Kbps
Upstream 1,199 Kbps
Connection time 3 days, 1:18:57
Data transmitted 823.76 MB
Data received 7.34 GB
If I carry on at this rate I'll be: 7.34*31/3.1 = 73.4GB in a month which is way more than the usual monthly limits of limited deals. (This works out at just 29kbp/s.)
And that's not including BT TV (where I'll be getting BT Sport over my broadband connection since it doesn't come via the aerial) where we'll make more use of catch up TV and watching movies online (Netflix maybe).
All of the limited deals go as far as ~25GB/month, so nowhere near enough for me.
That leaves me the (BT) options of "up to 17Mbps" for £13/month (what I have for 9Mbps and not enough to support BT TV properly), "up to 52Mbps" Infinity for £20/month or "up to 76Mbps" Infinity 2 for £30/month. (These prices are ignoring the various deals they have on, and not including line rental, etc).
For £10 a month extra I get my various big work downloads done in 2/3 of the time, which is good when I've got something urgent going on.
Work don't pay for it as I don't work from home full time.