Bill,
You're asking for advice, so here's my 2cents worth. Neither product you mention is designed for saddle skirting. These are excellent conditioners and waterproof products for boots and upholstery. I would suggest either neatsfoot oil or believe it or not, olive oil. I have been a full time holster maker for the past 45 years and I use only olive oil. Since the holster has been dyed, use can use it as a top coat, but apply it sparingly. You want just enough to set up the dye. You can add Fiebings saddle soap later on to maintain the flexibility, without making it a limp rag.