short cable length: does cable "quality" matter?

Well, at the risk of stating the obvious, I think it's important to use the cable that sounds the best for the least money. You are fortunate in that if you want to try more expensive cables, it will not be as expensive for you as it is for me ( 2.5 m a side in my setup ).

My audio guru once pointed out that the fun in this hobby was getting to hear great music on fine gear... that you paid bargain prices for. Your short cables are a smart move, then, both sonically and economically. In my experience,though, cable quality makes a bigger difference than cable length.

Given that most high-end speakers can be such a 'tricky' load to drive, I'd say quality does matter. That does not mean that you have to spend the equivalent of a used car to get it. Years ago, I had the experience of speaker wire that could literally 'tune' the sound of your loudspeakers by finding the best length. Granted, it was heavy-gauge, neoprene-jacketed stuff, and wasn't very good overall, but it did teach me about the effect speaker cable can have on sound. Maybe you could split the difference, and buy some moderately-priced wire in the exact length you need? Might just give you terrific sound.

In my own system I've found that 1.5 meters of really good cable sounded much, much better than 18" of budget speaker cables. YMMV