I've used the Two Little Fishies stuff, the Marineland HoldFast stuff, and the Rowa stuff you mentioned.
Of the three, the TLF stuff is my favorite. No cloudiness, but it'll make your skimmer go happy for a few hours. The Rowa stuff is good too, but I've found you can avoid that cloudiness if you do the initial mixing/kneading in a little container of salt water, separate from your tank. It also seems to have a slow set time compared to the TLF stuff, so I've "helped it along" by nuking it in the microwave for 10 seconds or so depending on the amount. (Just be careful... that stuff gets really hot really quick.) After the nuke, then I cool it off in the water again.
I've never had any corals have any issues with any of the epoxies.
The color of the "coraline" Rowa is great, but I guess TLF makes some that color too.
(Oh... and I'll NEVER buy the HoldFast stuff again. That stuff just seems the least "stickiest" of them all - not that any of them really have any stickiness to them.)