Even Paul will tell you the substantial difference in quality from an HRE Forged wheels versus a Spun Cast/FlowForm wheel. We make our own FlowForm wheels at a lower price point but at the sacrifice of weight and custom fitment options, so that would be the kind of comparison that you would want, but because the OP is asking for very lightweight wheels, that's exactly what we're showing off here.you can get forgestar CF5V's in 19x10 square that will be in the same weight range for about 1400 a set through forum vendors such as Paul. no need to spend 15-20% of the car's purchase price to get high quality wheels when there are multiple companies producing high quality wheels in the 14-1800 per set price range in similar weight ranges.
Feel free to post a picture of your 19x10 CF5V on a scale, I'd be happy to battle it out over weights since you say they're similar weight ranges. I'll do you one better, I'll tie one hand behind my back and post up a 20x11, and you can post up your 19x10 to see if they're lighter than these. Seriously, go for it, I'll wait.
Here's a 20x11 R101 Lightweight at 19lbs: