I've been running these AIO Water coolers for years now and never had one leak. Keep in mind, my PCs are on 24/7. I have two systems acting as servers (8 HDDs in RAID0+1 running Linux), and one of those system has a cooler that has been running constantly for over 5 years, constantly.
You are more likely to win the lottery than you are of having a leak.
Then 2 of my buddies that asked me what I thought of water cooling, and told them, and decided to get one anyway, and got leaks, never shared their lottery winning with me, what jerks they are

and it took one of them their mobo, and graphics card, and my other friend, his graphics card with the leak, so Ill just keep play the lottery and win it, then buy a water cooler

and I hope you knocked on some wood when you made that comment :O. I also read the comments on some of the water coolers, and yes they scare me when I hear them comment, it leaked in a month of use, or pump gave out in 3 months and fried my cpu, so again, my OCD, just keeps say, NO Jay, NO, keep using your hunk o metal

and watch that video I posted, for as I said, the one I picked out, yes may be big on the die, but so is the radiator you have to mount somewhere in the case, but it keeps right up there with the water coolers, so Im more then happy with having a huge one right there in the middle of my board. And I know what is in these things isnt supposed to fry anything, but it did, sprung a leak and shorted the stuff out. replaced the water cooling with air, and after replacing the board/graphics cards they leaked on, then the computers came back on, but once leaked onto, putting heatsinks back on, they did nothing at all, the one with the mobo, wouldnt even power, and the one with the graphics card would power on with a blank screen, then replaced the graphics card with one I had laying around, and then it posted.
As far as my heatsink weight, it really doesnt weigh that much at all, and has the best mounting hardware of any on the market to date as of yet of any air cooler.
So I guess what Im saying, is if you want better kick butt cooling then this in the op, though not really knocking it if water cooling is your bag, baby, but want some heavy overclocking, look into whats in my sig, it was pitted up again some big boys and held its own and no leaks, its air cooled, so you can do air, overclock, and not have to have water to do it, check out the video I linked in one of my replies, they tested it up against several water coolers. Yes its $40~ more, but mine is for serious overclocking fun

if not, and you gotta have water cooling, then YES, this is a STEAL for $40 shipped!!!