Has anyone replaced the elastics in their Freetimes? I have done the 4.0s without problem because you don't need to cut the fabric. I am nervous about cutting the fabric on the Freetimes. Will it cause them to leak? Someone please give me your experience before I attempt this!

For reference, this is a guide on replacing them so I know it SHOULD be OK but I am afraid I will ruin them!
http://www.cottonbabies.com/blog/replacing-elastic-in-bumgenius-freetime/