RL cashmere is made in China. The technology gap between European makers and Chinese makers has narrowed in the recent past and there are some good-to-better Chinese makers out there. However, the Chinese houses are infamous for adding synthetic materials or other fibers (like wool) to elongate fibers. The result is often a softer product, due to the cheaper, over-washed materials used; don't think soft cashmere is superior. I generally avoid Chinese fibers as there is no way to know where it was actually made, what QC processes are in place, etc.
I think of knitwear like I think of shoes: I wouldn't buy a "high-end" name just because that brand is known for making nice things. Think of it like buying E Zegna shoes vs. Crockett and Jones. Zegna is a great name and makes tremendous fabrics, but their shoes are crap (pardon Couture/XXX). Again, it's easy to be blinded by a name and a premium. So I generally stay away from the big Italian names when I'm going with knitwear (Kiton, Attolini, Gucci, Brioni, etc). I stick to smaller houses that specialize in, or only make, knitwear.
From the brands you mentioned, I've only owned a couple (Brunello Cucinelli and Loro Piana). Both are very nice, but also incredibly expensive. I've heard great things about John Smedley and Borelli. I've handled Malo on a few different occasions and, while some has been quite nice, I've also seen some single ply offerings that seemed quite lack-luster, considering their price point. I've never heard of "Trillion."
All and all I'd be wary about ordering something like knitwear online without handling it beforehand. Just like a suit or shirt, you really only get a feel of something's quality by handling it. If you're truly on a budget I'd keep any eye out on eBay and thrift stores for older (1960s-1980s) cashmere. That time frame is widely considered the golden age of cashmere and most everything made during those years, when cared for properly, will still look and wear nearly new today. Do some looking through this (and others) thread for some names to keep an eye out for.
Many of the purists will tell you that there are no excellent cashmere makers left. The expensive and difficult process of procuring cashmere properly, coupled with the invasion of bargain cashmere and the disposable nature of today's "designer" offerings, put a lot of the old makers either out of business or has forced them to decrease quality considerably. Pardon a few VERY expensive makers (think Hermès), there aren't many tremendous cashmere options out there.
