1800ma 1 cell, and use division to get ~500ma for 4 cells.
Except for discharge, it's about as decent as you could hope for in that price range. I wish there were a charger that did analysis for a low price from china. I'm somewhat hesistent to spend order of magnitude more on a Maha on the principle of the thing.
I've actually been researching cheap NiMH chargers on eBay for the past month. Not complete yet since I'm very slow.
That charger isn't bad although it advertises a very high (IMHO) rate for one cell. Most of the cheap chargers are limited by the PSU so do vary depending on the number of cells but some of them seem to do the same thing for 1 and 2 cells as 3 and 4 so aren't so high with 1 cell. In any case, for that charger if you don't have to pay in GBP you may find this cheaper http://cgi.ebay.com/2A-AA-3A-AAA-Rechargeable-battery-Quick-LCD-charger-/170513413479
You can also get a LCD 2 cell charger http://cgi.ebay.com/Q52-LCD-Super-Quick-Charger-AA-AAA-Ni-MH-Ni-Cd-/150403406238 where the rate shouldn't vary so much (well not at all according to the quoted specs) although it will cost more if you want 4 channels. On the other hand you do end up with 2 seperate chargers that way which may be useful in some circumstances.
On the other hand if you don't want LCD there are a bunch of supposed 4 independent channel delta V based chargers for cheaper e.g. http://cgi.ebay.com/Ni-MH-CD-AA-AAA-9V-Battery-Quick-Charger-US-9785-/160448900705 with only LED indicators (cheapest in my records I think)
Of course if you want discharging there is the Soshine Don mentioned in the other post about NiMH chargers that's on DX albeit semi-permanently out of stock (it comes in stock then goes out of stock again, so be prepared to wait potentially months for it) http://www.dealextreme.com/details.dx/sku.6152. This doesn't allow you to analyse the battery really just discharge it e.g. for cycling. If you don't want to wait that long there's also a similar Maxuss charger thats one dollar more http://www.dealextreme.com/details.dx/sku.35286 that's on eBay for about the same price as DX.
The Vanson BC-1HU is cheap, and like all Vanson chargers is often found rebranded as someone else's product. I think mine cost about $15 including delivery and will charge (and optionally discharge) AAA, AA, C, D and 9V cells.
Don't buy a high speed charger if you want to use the batteries for a long time. High currents of the fast chargers heat up the batteries and if the batteries become too hot, they have a much shorter liftime.
Make sure it charges each cell separately, the charging must stop automatic if the cell has reached the maximum voltage.
For me the Maha is the best charger, but it is rather expensive.
I too think that the Maha C9000 is the best aa and aaa nimh charger which is why I have 2. They are a bit expensive like Hobbyfotograaf said but $48.97 isn't too bad for a charger considered the best IMO.
I just picked up some cheap Sony chargers today to test out and give away to friends who are murdering their batteries with bad chargers. 4xAA/AAA NiMH, independent bays, smart cutoff, slow charging (360mA AA, 140mA AAA). 110 or 220V input. This one is at Amazon right for $5.49 and free shipping. Includes two "lite" AA batteries of 1000mAh.
Or this one which is a better charger with individual battery indicators and a refresh function that will discharge and then charge the battery $22.48, also has 4 2000mAh LSD's: