Hashnest S7 Hosted Mining vs S5: Which Is The Most Profitable At Present?Bitmain introduced trading for Hashnest S7 hosted mining on Friday night October 9. Based on the pre-sale price for hosted mining, which was $1923 for 4860 GH/s fair value would be .0016135 bitcoin/GH/s:As the internal chart at Hashnest shows S7 hash is trading above fair value at about .0019 bitcoin per GH per second. Not a surprise as speculators who bought an S7 to hash will be looking to sell for a profit. But is S7 the better buy than S5? Let’s take a look at recent price action for S5 hash:The price for S5 GH/s bottomed out on October 7 and began a short term uptrend while S7 price is flat.Based on current price and difficulty here are the numbers for S7 compared to S5:S5 hash would return 0.50% daily and the ROI would be 205 daysS7 hash would return 0.31% daily and the ROI would be 330 daysClearly S5 is the hash to own right now at Hashnest.Hashnest S5 is Preferable to S7 At PresentHashnest S5 GH/s not only has the better return but the price of S5 is in a short term uptrend while S7 hash is overpriced and flat. You can buy S5 hash and not only receive daily mining income but sell your hash at a profit if the uptrend continues as expected.However we do not expect the imbalance between S5 and S7 to last more than a few months. At some point the price of S5 hash will stop its increase and start to decline. We expect that will coincide with lower price of S7 hash. Be prepared to sell any S5 you may own and transistion to S7 hash when that occurs.Remember block halving happens next summer and at that time S5 hash may be “underwater” if bitcoin price does not increase. Maintenance fees could be greater than payouts. As long as you follow the Hashnest charts and sell your S5 hash when price starts to decline you will be fine. Take your profits and buy S7 hash before the block halving. It is also possible that Hashnest will have a new and more power efficient bitcoin miner than S7 by next summer.Hashnest Contracts ComparedThanks to pakerole at Bitmain Talk for 6 month outlook for profitability of the S7, S5, S4 and S3 contracts at Hashnest:The chart is based on bitcoin price and difficulty on November 1, 2015. Here is his one year projection:At current bitcoin price and difficulty S5 is the best choice. S4 may be slightly more profitable in the next few months but remember S4 can be harder to sell than S5 due to lower daily volume. If you had a large amount of S4 hash and had to sell quickly you might have to take a lower bid than you would like. Also remember as the bitcoin block halving next summer approaches you would probably need to sell all hashing contracts except S7. Unless bitcoin price increased significantly, after the block halving any contract but S7 would no longer be profitable.