Prosiphon cooler will die as all weird and nonsensical products. It has maximal cooling power of 200W, as shown in reviews. That is what 600g $40 direct contact 4 heatpipe air cooler can do.
Prosiphon is 3,5 times heavier (a true motherboard breaker!), FOUR times more expensive, FOUR times bulkier. At least in weight and bulk you get what you pay for. Not in performance.
I must disagree with you on what reviews have said about the Icegiant since I've ran mine before with my FX-9590 (220W Chip minimum) and temps were good under load - Very good in fact.
Had to adapt the mounting plate to an AM3/AM3+ setup and that was really easy to do.
Now I can run this one with anything from an AM2 to an AM4 and it's not a problem.
All the rest however you are correct about - It's a really heavy cooler and I can
only suggest it for systems that has the board
lying flat on it's back when installed like mine is but the performance is there at least.
Unless you're extremely sensitive to noise, IMHO the best choice is to buy something like the Noctua NH-D15S and use a super high quality fan (the one included works but you could probably get a fan with better acoustics) at a very low, inaudible RPM range. That way some air will circulate and you'll get better clocks, too.
This is the basis of my previous suggestion with the current setup as seen in the photos of it.
A better cooler combined with a low CFM fan of
at least 120mm in size at one side of the case/enclosure will make heat move along and out of the enclosure, like when a cop says "Nothing to see here - Move along" and it will work whether a different cooler is used or not.
Larger fans in size don't require higher fan speeds to move the same amount of air in CFM as a smaller one does so it's quiet in comparison to those.
To give reference about a larger fan:
I even have a case my dad is using ATM with a big 240mm single fan made into the side panel and it moves a ton of air, but it's barely audible at all.
You really have to listen for it to hear it running but the drawback of that one is the case it's in is narrow - You can't use a GPU card in the case due to inteference/contact from the fan so it's either onboard graphics or nothing with that one... But it works as said.
A wider case of the same size can make it work though and may do that one day but as is, my dad loves it and I probrably won't get that one back until he's gone himself - And that's OK.
He's 84 years old so you know if it was making any noise, I'd hear some noise of his own about it.
However I too have to say there are some good suggestions here that's not too expensive but will improve cooling - Combined with a fan as described you will see a real difference in temps across the board.
BTW I did see this and it's big yet it's not and is rated for about 38 CFM between all four fans so it should be a quiet fan set.
May not be what the OP is wanting for their own use but I'd bet someone else here would have interest.
4x120mm 240mm 5V USB Powered Cooling Fan for Router Rack DIY Audio Video Network Cabinet Server Cooling Projects and Equipment Workstation Mining Machine Laptop Cooling Fan Stand - Newegg.com