Yo-yo speeds on copper overlay (TPON) - should I wait for FTTC or cut my losses?

[#1]

Hi,
For the past few weeks the internet connection at home has been up and down like a yo-yo. To give you some idea of this, over the weekend the router was telling me it's got a 600k downstream connection, an hour later it dropped to 400k, by 3pm it was 100kbps and by 6pm it was slower than v.90 dialup. Then, at some point in the night, it seems to get a kick in the pants and start climbing up again. Sometimes the connection drops completely and when it finally comes back on I have to wait several hours for the ADSL light to stop flashing on the router.
It was good to see some news about the FTTC packages but they're dependent on cabinet enablement, and I am still waiting for BT to take their monumentally incompetent fat fingers out of their posterior orifices on that front. The enablement date for the cabinet I'm on, slips back almost every time I check it and barely a day goes by without an Openreach van man fiddling about with it. Currently it's back end of June, and I'm not even confident they'll get it done before Christmas.
ADSL is just too unreliable for it to provide my primary broadband connection. I need something better and I need it yesterday.
I've been offered the chance to switch over to a fixed point-to-point wireless solution that's ALREADY available in my village and has been trialed for a year - it is offering 50mbit unlimited for £23.99 a month. Obviously if I go with that, I won't have any reason to maintain the ADSL connection unless I drop down to the minimum package and have it as a fallback solution.

The alternative to that, is to wait for FTTC - but with the push backs on cabinet enablement, I'll probably be able to buy Duke Nukem Forever before I can get FTTC. Neither PN nor BT seem interested in explaining how come the other cabinet in the village is already up and running with FTTC customers, but the one at our end of the village has already been pushed back by more than six months.
If you were in my position what would you do?

[#2]

When you say 50mbps is that 25mbps download and 25mbps upload as WiFi specifications tend to add these together for a headline speed.

[#3]

No... the package is £23.99 for 50mbps down 20mbps up - Unlimited Usage. It is based on 802.11a/n in the 5Ghz range, and should scale up to 150Mbps per endpoint.
(edit: the technology should allow for a 75 megabit symmetrical connection between the property and the base station. At present the pipe from the base station is not fat enough to deliver that, so the packages are scaled; the unlimited one is the most expensive in the domestic bracket but presumably has been priced to ensure that if enough subscribers take it up in preference to the low-end products the funds will be there to increase the pipe and meet the requirements).

[#4]

I suppose the first question is do you need a fixed telephone line at all.
If you have a mobile package you could junk it.
Alternatively could you switch to VOIP

[#5]

Strictly speaking, no I don't need a fixed line.
Many people in our street have already ditched the phone line completely! If they need broadband, they get a far better broadband service from their mobile providers than they can get through ADSL.
There's not much point having a fixed land line that delivers good voice + fax if connected to the 80s TPON, but if you're connected to that you cannot have ADSL. One house in our street did get ADSL but then complained the voice+fax line quality was terrible; BT resolved that by putting them back on the TPON and killing the ADSL connection.
On current fixed line technology you can have good voice+fax or bad voice+fax+ADSL. There is no "good" wired solution and won't be till we're FTTC enabled, but there are two wireless alternatives (mobile and fixed 802.11n) which deliver better voice AND better data than the copper overlay stopgap.