Planning on installing about 800ft^2 of engineered plank on a slab....myself for the first time.
I'm hoping that I can float the flooring (do NOT want to attempt gluing ).

I seem to be seeing, as I browse online, that the click-lock methods can vary quite a bit. Some are good, some really....suck.

So, looking for advice/recommendations.
Is wanting to go with floating this floor not a good idea?
Any particular click-lock systems I should be steered toward? Any I should avoid?

Longer planks can be a problem to keep in alignment when tapping a clic-loc together. I think a six foot long plank is the best. You should use a plank that is at least 5 inches wide. There are different type of foam that lays down first, I think the more dense rubber type is the best vs. open cell poly-ethelyne. Be sure to read the directions that come with the product.

First, thanks for the reply.

Question on the underlayment - in curious about your recommendation. Can you expand on that?

I'm NOT a fan of clic lock on hardwood and especially strand bamboo.

On the underlayment I always use Sound Solutions even under laminate and cork.

http://www.healthierchoice.com/sound-solution.html