Have you personally used repetier host? Recently like since the 2.0 update?
yep. Like I say, it's okay.
Cura is also okay - once you figure out that you need to add gcode for a bunch of stuff s3d does via menus. Some stuff I just couldn't get it to do.

And why can't a cheap printer also be a quality printer ?
Mine is :-)

Is s3d worth $150 - probably, I only paid $80 a few years back, so that wasn't a decision I had to make. Though why people always go on about the supports - I don't know.
Not been overly impressed with them myself. And the dual head printing just doesn't work for me. I have tried everything else, even propriatary software. One of My motto's: You never know if it will work till you've tried it :-)

Still looking for laser engraver software for deltas - don't think I need it - but if I find any and it's easier than the method I've already worked out - great.

I'm a great advocate of free and opensource software. s3d is the only software I've bought, probably in the last 15 years.
Like everything it's got a lot more expensive. Would I buy it today ? probably not, and I didn't tell you this, but even the latest 3.1.1 version has been cracked and is available from file sharing services - so I've heard ;-)