Hi coast,
They are very similar in their designs in terms of their layering options except SleepEZ has a wider range of the type of latex they offer in each layer. With SleepEZ you can choose 100% natural Talalay, blended Talalay, or 100% natural Dunlop in any of the layers while Flexus offers 100% natural Dunlop in the base layers and blended Talalay in the top comfort layer.
There are also some differences between their return and exchange policies and their pricing and as you mentioned in their covers.
No … it wouldn’t be an issue.
Both of these would make a great final choice.
Phoenix