For me personally, I am not overly excited about Shellac's colours, and it's mainly good for healthy natural nails. I use CND Brisa gels and Creative Play, but saw no reason to use Shellac over any other brand except the short soak off time - but I only do enhancements (topped with gel polish often) anyway, so I wouldn't be soaking it off anyway, rather I am filing it off.
If you are having chipping problems it could be down to a number of reasons. I will try to list a few things to keep in mind. Hope it helps, let me know if it could be anything like this?
Is the natural nail healthy?
Did you buff the natural nail? This will usually lead to chipping because it weakens the nail.
Did you remember to dehydrate, properly cleanse?
Base coat not too thick? Capped the free edge?
Thin coats, not thick? Sealed with topcoat of the same brand?
Cured correctly? As in, you are curing with the correct lamp to the brand you are using? If you are not, then that is maybe the culprit.
Client has her or his hands in water a lot? This would do it, too. Water is such an enemy! I hate it when a few select clients come back with 3-4 nails missing, and I'm wracking my brain trying to figure it out because they insist "it just popped off". Right? Well no. Last time during the service, she accidentally let slip that she had been away and had gone swimming in a chlorine pool every day... and she had told me plainly "no" when I earlier asked whether she'd been exposed to water a lot, since there was no damage on the naked nails. Clients will lie, and they do lie a lot. So it's useful for us to deduce what's going wrong.