Strengths: 3 containers with switchable lids (in case one gets stepped on), and a spare valve to create your own if these containers aren't big enough, or you want a larger tray for prepairing / flavouring mixers.
Weaknesses: None, they do their job and do it well, especially at these prices.
Overall: Exactly the same as the ones sold in many tackle shops....but they charge more and you only get one container. This kit is very affordable and can be used for many fast bait preperations. Not just for expanders, even for the specialist or carp angler using boilies, keep them fresh for longer in one container and rehydrate air dried ones to help spead breakdown times and flavour leak. Flavour and soften dog biscuits in seconds.