I always think it's better to eat more to be honest. Using the Syns helps to avoid those feelings of deprivation that can occur if you don't use many Syns at all.
Some people use 5 a day during the week, but then use more at the weekend so they don't feel like they're missing out on something, either alcohol or a takeaway or something, whatever they feel is necessary.
Don't feel like you have to use all of them everyday though, if you don't want to use them, don't force them. But just know they're there if and when you want to use them