S90v is a bit harder to resharpen, but I don't feel it's significantly harder to maintain a sharp edge, it's only more work if you want to re-profile the edge or need to bring back a very dull or damaged edge. I also wouldn't turn down a knife with S30v steel at half the price, S90v isn't twice as good as S30v. These days if you are going to spend more than $150 on a folder, it should have premium edge holding steel. There are too many great production knives available with higher end blade steels (S90v, S110v, 20cp, 204p, M390, etc.) that hold their edge significantly better than S30v, S35vn, VG10, N690, 3v, CTS-XHP etc. etc. A knife is used for cutting after all, and most people are not experiencing chipping/breaking with any of these steels in general folding knife use.
It's well worth your time to research and learn about the properties of various steels for your intended use. For example I see no point in buying a folding knife in 3V or CTS-XHP because they give up edge holding for toughness and I'm not seeing damage to my knives in steels that hold an edge much longer. If I was then of course I'd lean to folding knives with tougher blade steels (or change my edge profile).
Worth is a very personal decision, you'll see production and custom knives that cost $500+ that use relatively boring poor edge holding steels. For some people that are into the design, the maker, love sharpening all the time, etc. cutting performance is not at the top of their list, but for me I'm very much a function over form person. So if someone wants to sell me a $500 folding knife, it better blade steel with a focus on edge retention. It's no different than a $10K Rolex not being able to keep time as well as a $50 Casio, people don't buy Rolex watches because they keep the most accurate time.
