Depending on how much power you're trying to achieve, I would say its worth it for the efficiency benefits. But they do make a bit more power than the gen 2s. However I would suggest getting as gen 5 blower, they are truly a big upgrade. Hit me up anytime if you have questions about any of the setups. Lethalperformance.com
Word on the street is the upgrade from gen 2 to gen 3 was pretty substantial. Gen 3 to 4 not as big of improvement. If you're on the stock motor a gen 2 can window your block. Gen 5 is nice not just because of the rotor efficency increase but also better IATs due to the bigger intercooler. The gen 2-4 look better under the hood in my opinion.