One of the reasons I don't use dumbells much anymore is because I work to failure on some sets. What are the alternatives to dropping if you don't have a training partner. Flat dumbells can mess you up if you try to ease them on the floor out to the sides. The best bet is to hope that you can bring your knees in close, set the dumbells on there, and then bring yourself back up. The reverse for the way that I set up for the lift. This is usually what I do if I'm not training to failure on a set.
Having said that, there's nothing worse than working out with a pair of dumbells that look like the plates are gonna fall off. Scary shit.