This depends on your skill level with re-terminating cables, but another very viable possibility is to simply ignore the connectors that come with these lights entirely. Cut them off and put on better ones that you prefer. Micro Deans for example.
These are cheap lights. Great value, but lower on the quality scale so DOAs are possible. Get an unmatched or faulty connector? Replace it. Need new batteries? Buy cells from DX or similar. Get a bad charger? Use something better. Use a hobby charger - then any batteries can be charged and their actual capacity and health monitored. Purchase some cheap 18650 chargers just to strip out the electronics and use the holder with a good charger. Or if you search electronics suppliers you can find 18650 cell battery holders. And on the topic of purchasing battery holders, these can replace the ones that come with the lights. This gives flexibility to add more parallel cells and give longer run time. Or you can run your light(s) on LiPos from Hobby King or similar.
There are so many options...