A quartz timex watch is about $20. A rolex submariner is about $6,000. In all actuality (and even die hard Rolex and high end mechanical watch experts will admit) a cheap quartz watch keeps more accurate time than an expensive mechanical watch. Even at $6000 it's hard to find a submariner in stock at a jeweler's shop. For guitars you can buy a squier stratocaster or epiphone Les Paul for $250 and under, which is made of pretty much the same wood as Fender Stratocaster or Gibson Les Paul. For a custom shop made Fender or Gibson you can easily go into $5k for one of those, and even at those prices there are still people getting in line to purchase.
IF the question is "whether it is worth it" to buy an actual nemesis? Is it worth the money to buy a real Rolex, or a real Gibson or real Fender (or a real Armani suit over a Men's Wearhouse, or real French champagne over $3 paper box wine)? The answer is your k100 works just fine, and gets the job done pretty close to a nemesis. Is there a difference between a k100 and a nemmy? The nemmy is really quaility made and you can see the quality when you touch it (finer engraving, finer threading, smooth button). Is it worth the extra money? Depends on how bad you want it (or a rolex, or a stratocaster, or an Armani suit, or French champagne). As for me, I bought the real nemmy.