Think it all depends on what salt you're using, and how low your nitrate test kit can measure. I think pretty much all salts will put some amount of nitrates into your water, whether you want them or not. My Reef Crystals, mixed with DI
water, gives me 0.5ppm nitrates - which pretty much matches the latest salt water test results floating around the internet. So I could do water changes until pigs fly (naturally), but I'll never get anything less than 0.5ppm.
With that said though... I agree that as close to your "pure salt water" baseline as you can get is best. Most I've ever had in my tank (well... since things stabilized after I cycled) is around 1.0ppm. So in my book, 10 is pretty high. But that's just me.