Thanks everyone for your help so far
I have read also about getting a set with the 7mm. I am not sure how much I would use the 3.5 4.5 5.5 in the bigger kits I linked to but all kits seem to come with a 2.5.
Standard kits don't seem to come with a 7mm they are 1.5, 2, 2.5, 3, 4, 5, 6, 8 and...