Clone batteries typically have a somewhat higher early failure rate and generally decline in capacity faster than originals.
Clone mAh capacities are usually no better than or are worse than originals - regardless of what the labels say. The higher the claimed label mAh the more likely it is that the manufacturer and product is suspect.
An unloaded LiIon battery should retain its voltage almost unchanged for long periods - at least many months. Clones and originals should be no different in this respect. Any battery that loses capacity or terminal voltage rapidly when unloaded is highly suspect. Note that some systems place a continuous light load on the battery when in standby or sleep modes.
My experience with clone LiIon batteries is that they are usually somewhat somewhat inferior in lifetime performance than are original batteries BUT that their very much lower price means that they are much better value for money than original batteries.
Lithium Ion batteries can have major reliability issues and worst case can "vent with flame'> This is not an explosion but comes somewhat close on occasion. The total energy in the battery is released in a flaming over 10 to 10s of seconds. If this happens inside your camera you'll be needing a new battery, AND a new camera. Repair is unlikely to be a sensible option.
Name brand manufacturers are not immune from such problems. Various 'top' manufacturers have issued recalls of probably millions of laptop LiIon batteries over the last decade. These are numerous horror stories available and graphic youtube videos of laptops and other devices incinerating or having been incinerated.
All that said, I'm an EE and have quite a lot to do with batteries. I have never seen a LiIon battery self destruct out of captivity and do not know anyone personally who has had it happen.
I have purchased 20 to 30 "clone" LiIon batteries for digital cameras in the last 5 + years and am happy to use them.
BUT - if you do have a melt-down, and odds are you won't, if it's a Canon battery you MAY be able to persuade them that they should replace your camera. If it's a Horse-Radish brand battery (as yours are) or some other lesser know Asian brand, then odds are the endor or manufacturer (if known) will be unlikely to replace your camera. Now, it MAY be that I am incorrect in my assumptions re Canon and/or re Horse-Radish. You need to decide the merits of this aspect yourself. It also may be that your insurance policy will cover damage of this sort. Or not. Again, I am happy to use clone batteries and I've never seen or directly heard of any vent-with-flame problems.
PERFORMANCE: Clone batteries usually have larger claimed mAh capacities than original versions. You can pretty much guarantee that they are lying. If they lie about capacity it may not be a good sign re their other business practices :-). While it is possible to get more than typical capacities from a given size of LiIon cell, this is usually done at a cost. If you are making low cost product it's a lot easier and cheaper to print a lying label than to fit in more Li metal or afford and use industry leading edge practices that safely give more capacity.
LiIon batteries have two main capacity loss mechanisms. They lose capacity with each discharge / charge cycle of use, and they have a "calendar life" where they slowly lose capacity "just setting" even if unused.
My experience with clone LiIon camera batteries (mainly for various Minolta and Sony DSLRs) is that initial capacity is about the same as original, they may lose capacity with use somewhat faster than originals, and they tend to have a noticeably shorter calendar life.
That said, value for money they usually give far more accumulated total mAh capacity per $ than original batteries. Overall they are VERY substantially better value for money than original batteries and I am happy to use them and have never had any problems with them.
Most clone batteries that I have met have not suffered catastrophic failures in capacity or lifetime. However, some brands of clone batteries have a certain percentage of their batteries fail totally after a very short time or lose capacity at a very high rate. Some sellers, even on auction sites such as ebay will replace batteries that fail or fall well below specification within a short period. Those who do usually offer 6 months warranty. You need to determine the policy and credibility of your vendor. I usually buy from a vendor who I know is of absolute integrity (a retired surgeon who sells photo gear as a retirement hobby). He will tell you the likelihood that a given brand will fail and will unquestioningly replace any that fail catastrophically. Odds are your vendors will be a little less inspired than he is - but do check.
Update 2 years on:
Update - April 2015:
I just bought 3 x clone batteries for a Sony A77. They all worked OK at first but after 5 to 100 photos taken all 3 cause camera to give a "incompatible battery message. I have used MANY clone batteries with a range of Sony and a few other cameras and never before seen this happen.