we've actually got a couple monster 1.5m in stock at my shop, they're lower grade mostly, though and potentially old, honestly it's only useful if you're stacking HT components directly on top of eachother. 1.5' is SHORT... heck 3' in a car is relatively short.
I started with knukonceptz cables, nad have since replaced them all with higher quality ones, the KK rcas all sorta started to come un-soldered at the ends and such after time it seemed. Also it's seemed that the coating on most of my kk wires has worked its way loose. I wouldn't entirely say that Knukonceptz wires are bad, as it might jsut be a price point issue, but I do know that I wound up pulling things up to have to re-wire. WHich I don't like.
As far as which ones to go with, I'd genereally recommend to not get TOO overboard, but don't buy bottom of the line either. Additionally, WIth my mixed bag of higher end PG and monster rca's, the nicest go to my midrange and highs, midbass gets similar, and bass gets the shortend of the stick. My digital coax coming from my computer is likely WAY toonice for what's necc, seeing as digital signal is digital, just 1's and 0's noise introduced is minimal and shouldn't effect signal clarity.