I tend to avoid leather conditioners on vinyl coated leather as it just attracts dust as the majority of the product is just sitting on top of the seat. You could argue a small amount of oils end up through the cracks in the coating, seat and stitching but I never found it worth the effort given the dust issue.
There is an easy way to test if your leather is vinyl coated - just put a small drop of water in an inconspicuous spot. If the water absorbs into it, then a leather conditioner will work well as there is no coating. If it sits on top like a little bead, the leather is coated and you would be better saving your cash.
I always use a good quality leather cleaner though to ensure I don't damage the coating and to keep it looking its best.