The general consensus is the SLS is good value for money when comparing $$$ spent to improvement in performance.
Just a couple of years ago, the standard kites were all anyone was riding and they were brilliant, and weirdly enough, still are

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Enter SLS. The value and performance are worth it for the average intermediate kiter who is venturing into kite loops and know how to "throw the kite around" with a degree of precision. For high end kiters, the DLAB is the next level. I personally don't see the $$$$/Performance value ratio working in many peoples favour unless you are hunting big air and multiple kite loops, or are an expert kiter who can really extract the benefits. Or maybe you are minted AF and don't care about the cost, then buy whatever you can afford and enjoy..
Bottom line? Is the standard kite dead? No, not at all. They were a great kite and still are a great kite. They aren't going to be holding many people back in terms of performance and I know very few kiters who can absolutely wring every ounce of performance from a standard kite. I've seen highly skilled kiters on older kites absolutely kite rings around people on higher performance kites.
It's amazing to have the three levels of performance available at varying levels of cost. All three are totally viable. Just depends on your own personal circumstance and needs.DM