Okay here's my ramble...
If you read the labels or on-line product descriptions, almost ALL of the leather care companies nowadays are saying similiar boasts about their own products, that they are water and/or lanolin based creams or sprays containing only natural oils, having UV protection, ph balanced, safe to use, and effective in cleaning and/or conditioning, protecting and restoring needed oils and/or hydration. Virtually none of them anymore are greasy petroleum based, etc. Don't believe me? Check out the descriptions of the products on this page:
Leather Care - Clean, condition & protect leather upholstery with premium, pH-balanced products by Pinnacle, Wolfgang, Lexol, Leatherique, Connolly,
At the same time many of the same companies say that most or all the other brands on the market are greasy, oily, harmful to your leather, etc. Now that just can't be true, that everybody has the one and only safe product and effective to use, and almost everybody else doesn't!
As I understand it, even many of the rejuvenating oils such as Leatherique and Leather Vital use natural oils rather than petroleum base. Consequentally these are also safe and effective to use in the right situations.
So I ask just what are all these harmful products we all need to be wary of? I've kind of come to the conclusion that some products are more effective than others in certain situations. Some are made with a little better care, chemistry, possibly ingredients (which is still no guarantee they will work miracles for every situation). Still others are just run of the mill, effecting some level of cleaning and/or conditioning. But very few are actually harmful to your leather. Rather they just don't do more than a light cleaning and moisturizing.
Lexol for example is not a bad product. I think they changed their website now, but they used to have a picture of a couple chemists in white uniforms describing the history of when and how their secret formula was achieved. Kind of humorous, yes! But in spite of their being more run of the mill, it can't be argued that many swear by the results they get from their products.
So my conclusion? Use what works for you in the kinds of situations you commonly run into. That apparently involves trial and error, not just believing one person or one company's claim to be the one and only right product.
To the OP: For new leather I don't believe you don't need anything heavy duty like Leatherique. Regular cleaning and light conditioning or protecting should suffice.
My disclaimer: I'm not a chemist, but I have some experience and I can read product descriptions. Not being a chemist, I may have some detail or explaination wrong or wrongly worded, but hopefully you guys get the gist.