In my mind, this is currently the best miner for Litecoin:
Basically what you want, is the most hashing power that uses the least amount of electricity. Currently, I do not know of a more efficient miner than this one.
Depending on your budget, you would purchase one or more of these.
For people that have been mining Litecoin for years, they likely began with CPU/GPU mining (getting a motherboard and loading it up with video cards), then purchased KNC Titan miners (since most others at the time were scams or nowhere near as efficient), then very recently had the opportunity to buy an A4 from Innosilicon, and now the new king, the L3 from bitmain.
Again, it's all about hashing power versus electricity. Getting the most, using the least.
Hope that might help.