In the 9 years this forum has been around, I've seen one person use Ability Systems Indexer LPT on their machine.
Back then Mach was $100, and a comparable package from Ability Systems was about $900. The gap has narrowed a little, but the 9:1 cost ratio allowed Mach3 to take over the market.
It supposedly works very well, though, from what I've heard in the past.
There are other options besides Mach3.
And several others.