I myself run a SaltPlus Trapez free coaster. I have had it for about 2 years now, as it came stock with the bike (WTP Crysis 2014). I have never done any maintenance whatsoever on the F/C, aside from a tear down and a simple re-grease every year (without replacing any parts, bearings, seals, you name it).
I do abuse it, and I was giving it hell when I was learning fakies and full cabs, half cabs... Treating it like a cassette: I used to engage it before popping behind. I didn't realize my mistake back then but now have learned real free coaster full cabs... It was also prone to a lot of side loading from all the full-momentum fails of hop tail whips and the occasional sideways hit (from a moto whip) on dirt.
I ride primarily dirt, which is quite dusty in this time of the year (in fact, 2/3 of the year). I also ride street sometimes, with some 4ft drops, (but nonetheless smooth riding). I regularly take it out of the house by a 2 ft drop everyday (and like to repeat the procedure). However, I don't run pegs...
Now, for your questions:
-The hub is silent, and when i mean silent, i mean dead silent. There is not a single sound, mate. When you are coasting, you are riding on your bearings and there is no ratcheting sound. Think of a f/c as a reversed-cassette. It's ratchet teeth only engage when you pedal forwards, and as soon as you stop (or as soon as the body of the hub goes backwards), the teeth spring back to lying low. This is great as all you feel is the smooth pumping action of the tires, on jumps, in bowls.. It also makes you stealthier street-wise. However, it is quite a pity, as I just LOVE the sound of that ratcheting, especially on a BMX (it is what makes a BMX a BMX after all).
-The SlatPlus Trapez in my possession is durable. it has not failed on me...yet... NO worries as long as you don't do a Eiffel-Tower drop.
-I don't like slack at all. This is quite weird for a F/C guy, but hey, I don't like slack, seeing I do dirt and want max engagement-when I need additional speed (who wants to case a jump and hit his ball sack anyway?). The minimal slack position gives a 1/6... or bit more than 1/8... crank before engagement...hell, take it this way: your bloody foot will go down about an inch before the thing engages. After a few months (and heck-even 2 full years) with that slack, it's perfectly fine. It also makes you anticipate stuff and make you know your bike better.
Advice?
If you want this F/C, don't get turned down by the price. It's that low because it is from a KHE hub design, so the engineers didn't have to crack their skulls designing it (just tweaking it to turn out better), and-and this comes first- it's a bit old (2 years does seem long in the BMX world -my view-). Quality is top-notch: german engineering is one of the highest quality (if not THE highest) in the world. Sorry yankees.
You will not be disappointed by this hub. If you are, then you can spank my ass and get my bike for free.
It doesn't matter where a train goes. It's decidin' to get on that does.