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Question: How long do these batteries last in comparison to OEM ones?
Document: Purchased for new Olympus camera and the batteries last about as long as the OEM. Haven't actually calculated time/clicks, but with 2 backups I have no problems. The charger is small and convenient that I can leave it in my bag.Update: At some point the charger stopped working (no LED and drained battery didnt charge). I did try putting the Wasabi battery into the OEM charger for about 45min (LED on) and it worked.
I bought this charger specifically for the built-in flip-out prongs. The stock charger that came with my OM-D has a pigtail cord that takes up too much room in my kit and is a hassle to use. This one is a bit thicker and isn't as solidly made, but is smaller than the Olympus charger + cord together. The batteries seem to work OK but don't last as long as the OEM Olympus battery, despite their claimed greater capacity.
I have run through about three recharges on these batteries and they do a nice job but clearly don't last as long as the OEM. It is a slight pain that they require a different charger than the OEM's, but I always remember that I paid half the price for two of these for every one of the OEM's.Gave 4 stars for not lasting as long as the OEM's and requiring a separate charger. These are minor details in my mind for the price savings.Yes I would buy these again.
After having found this on Amazon, I cannot believe how close I was to paying nearly $50 for an OEM Olympus battery for my OMD EM5.These batteries work, they last just as long (or near enough as makes no difference), they come with a smaller, more portable charger that works on your OEM battery, and it includes a car charging option.FOR HALF THE PRICE OF ONE OEM BATTERY.You've already made your decision - if you need more batteries for your camera, buy this.
I was a bit reluctant to purchase this product as it seemed very hit-and-miss based on other reviews. However after using the batteries for nearly a month , i am very happy with the purchase. As far as how long they last ? Well, I've shot over 1,000 images with one battery and about  for a continual time-lapse project,  and several 10-second videos and there are still 2 of 3 bars left on the battery.
These batteries lose the race. I should have bought a second Olympus battery, even though more expensive. The two reasons are: this doesn't last very long. After 50-100 shots, off a full charge, it dies. Maybe I just got lemons but the Olympus battery is good for 3-4x as many. Second, the Olympus charger and this one are not interchangeable. So when traveling, you need to carry two chargers. That's a pain too.The lesson... don't cheap out.
I actually ordered two of these packages knowing the OM-D EM-1 eats batteries like a Russian tank. So far I have been getting about two days of intermittent use (with battery grip) before I have to swap in the other set. I suspect you could get a 3 hour long photo shoot done before running them down. If you need to get through a 6-8 hour wedding I would order the official Olympus batteries as they tend last longer.
Probably doesn't last quite as long as the Olympus-branded lithium battery but you get two of them for half the price. Other than shorter life I see no difference in performance.
I picked up these as a backup for a trip out of the country. I used them a few times before the trip and they didn't seem to last as long as the Olympus battery. Sadly, on the trip, they did not hold a charge hardly at all and I was left without a backup. Lesson learned.
Who knows - they could say "NASA Mars Rover cells" or anything else for all you can tell. As noted, the cells don't have a chip so the camera won't show the level of charge. Mine charged for about 10 minutes each. Is that now a full charge? How long will it last? Who knows?All-in-all, cheap and disappointing.
Answer: Not quite as long but the bundle is well worth the money considering you get an additional charger, car charger and 2 batteries.