Yes you nailed it. There is no comparison between bitcoin and PayPal as bitcoin has so many features and jargon free which we cannot find in PayPal and cannot expect as well, In other words PayPal is a failure method and Bitcoin is the future as day by day more and more merchants have started accepting BTC and more countries are going cashless so there is a lot in store for BTC which PayPal can never achieve.

@metalmag = For Mining, if you need to use AC, you're not doing it right.  Especially if your region upper temperature is that cool.  Again I'm in the 40C in the summer and others are even higher in Arizona and we can do it fine.  Even if you have free Electricity the cost of buying, installing, maintenance, etc is very high.  Let's do some quick math.

Assuming Free electricity.

10 Rigs = 4 TON AC @ $4-7K each depending brand and SEER levels installed.
100 Rigs = 4 x 4 Ton AC  $40-70K.

1 x 4 Ton uses at peak up to 60AMP.  So you're wasting 600AMP just for AC alone!  Now you have to factor in that you will need around 600-800AMP more for your 100 Rigs so the total is up to 1400AMP.   Even Commercial space the transformer may not be powerful enough to handle 1400AMP as you're sharing with other tenants.  You can request for more power if it's available but they will charge you for it.  Now this isn't even taking the consideration of the 80% rule which means you really need at least 1700AMP.  This is taking you into Industrial spaces which requires very large warehouses.   So you're talking about something you can achieve for less than $40K which includes 600AMP of power to drive your rigs into something well north over over $200K and require special zoning to accommodate.  If you design your environment right, you SHOULD NOT need AC.  Mining is a Mathematical game.  Even at 3cents / kw, you won't even be able to compete against someone with 10 cents KW even you have to use AC.  I would invest that money into more RIGs and a better layout / exhaust strategy. If you have that kind of budget, it shouldn't be hard.  To win in this game you must keep your cost low and invest the rest into HASH.

@yslylung - Yes Finksy just got his 150 Picos in.  Your price is very competitive for a custom solution.  Finksy's cost is actually still lower so there's a small margin for reseller on top but his goal is to keep the cost as low as possible for the community.  He's sending me 20 units to test for my different Prototypes designs.  I have 10 of the HP 1200W including the V6 breakout boards plus more 4KW to play.  There's never a 1 size fit all solutions and always pros and cons with every options.  The HP solution is best if you can get them in bulk for $20 or less each as there's breakout boards $25-30, Pico $30 and cabling cost $18-25.  That brings you to about $105 for the normal consumer.  People will always argue that you can buy a ATX for almost the same price with better future resales, yadda yadda.  Maybe you can during hot sales but the cabling and configuration will not be as sexy.  The issue with this solution is that many people in America use 120V which this PSU can  only deliver 900W vs the world on 240 which this PSU can deliver 1200W. I don't have this issue so I'm not concern.    Also the HP 1200W have only 1 TINY fan, I'm not sure how well it can handle the heat but man does that fan make a LOUD pitch noise!!  This thing is definitely not something I want to run inside my house.

For large miners the 4KW is important as they don't want to rearrange rigs after it's installed in the RACK.  They also want be future proof and plug things in and never have to really think about power usage later one.  Heck most people didn't even know that ZEC and ETH first version and current version consumes WAY MORE power.  So if they're sizing based on original estimates, they're screwed.  However as you said, if you have a PSU go down, you're not just affecting 1 rig but multiple.  That's the downside, the upside is that each breakout board and PSU is so cheap, there's no reason why you shouldn't have at least 1 spare bundle if you're a large miner.  Swapping is super fast and simple.  Efficiency for PSU is also better when you're using less than 70% of load and that will be harder to do on the HP.   I like bother solutions and at the end of the day, paired with PCI Risers and Picos, I'm really liking the Server PSU setup so so much better.  No more clutters.

I have design prototypes that will take advantages of both the PROs on each solution.  At the end of the day, if you're a large farmer, you will have a variety.  There's no solution that can meet every need.   But I do think that once people see more of the cool server PSU and PICO designs now that we PCI Powered risers, they will LOVE TO GET their hands on these PICOs.

The air is pulsed from the ground through grilled plates that replace the normal floor plates and pulled by negative pressure, made from the racks intakes and the hot aisle separation/ceiling air-pull, this is the most efficient design as air cooling goes, and the sad part is that you have plenty of datacenters that aren't respecting it fully, even though it has been invented for nearly 25+ years now. You also have some system variant, but the principles are the same.

Cryptocurrencies are vastly superior to typical fiat currencies, but they are nowhere near as convenient at the moment. It will take a long time until a bitcoin world appears. For example, if you wanted to pay for a beverage like a Coke with Bitcoin, as of now it would be take around 30 minutes for the transaction to be confirmed, not to mention having to input the restaurant's address. It is just much quicker to hand over a note and get your Coke instantly.