UPDATE: Well, after 12months and 1 bloody week

, my portable sensor bar packed up

. I swear they make things to last just over the warranty period nowadays

.
Anyway, What happened was the right LED bank went kaputt.
I had to resort to buy a new one.
Queue Zavvi.....where they have a rival in stock, the Madcatz Sensebar:
As you can see, it only has 3 LED'S each....so that's just over half as powerful as the 4Gamers one.
However, it seems to work with no problems.
I also like the fact that rather than being "ultra bright blue", the LED is a much more discreet dim green (goes red when power is low).
Apart from that, it does look a lot more flimsy than the 4Gamers one

.
The best feature is the power save feature.
You simply set to the time you require and that's it (only works when powered by batts of course). Once the time is up, the LED starts blinking. If you leave it alone, it will auto-shut off. If you press the reset button on the right, it will start counting down once again from the time you set on the left. Choices are 1hr, 2hrs and 3hrs.
This should help prevent any "forgetting to turn off and running down the batteries" syndrome that I used to get with the 4Gamers one

.
...but the best is yet to come:
Notice that small switch at the back? You can switch this bar from tru portable use to being powered by the Wii....which means you can effectively use it as a spare Senderbar and forget about batteries all together.
Also useful if you have set up the main sender bar in the main room and occasionally take the Wii to another room to play instead.
It does this by coming with a connector with a male nintendo plug at one end for the Wii, and a "standard" round plug at the other to go into the bar:
Overall, quite a versatile bit of kit.....made even better by the fact that it's currently only £8 in Zavvi

.
Build Quality: Very poor I must say. Looking at the piccies above, this is a brand new bar and even the plastic moulding has been cut badly (look at the hole for the switch in the 3rd photo). I'm not very impressed and think overall it looks more like some market stall tat than a high quality item (like the 4Gamers bar.....well built and nice and solid to boot).
Looks: I like the more discrete dim LED but that's about it
Price: £8 isn't too bad, but given the build quality I think £5 should be more like it.
Power: Less powerful than the 4Gamers one by far (this only has 3 LED's per side, the 4Gamers one had 5).....
Batt life: ......but then again, that means it takes fewer batteries....4 AAA = 6v. (4Gamers takes 6 AA = 9v).
Even though AAA can be harder to find I think only using 4 is a slight bonus.
Warranty: At least this apparently comes with a 5yr warranty. However, you have to pay to and return postage yourself....hardly worth it for a £8 item no?
Overall: A decent bit of kit. The build quality looks so cheap that I would still rate the 4Gamers one higher, but this is still worthy of a punt if you want a spare senderbar for you Wii coupled to a portable one.