Both the HKS and our TiAL unit are about the same price, retail. The HKS unit is a good bypass valve; they make good products for the most part. Because of the 50mm valve, our valve flows more, faster than HKS valve.
There is a direct knock-off of our BOV being manufactured by TurboSmart, in Australia. They've altered the design slightly to allow for more valve lift, so technically, the TurboSmart unit can flow more volume while fully opened. I have a "sneaking suspicion" that they won't be making that valve for much longer

.
Bottom line: our gates and bovs rock. Synapse sucks; HKS is overpriced for anything good; TurboSmart is... well, not turbo smart.