Following was asked on the Enigma Telegram by user Mr. Garbonzo:
“Will this testnet allow us to get an idea on the speed of a typical tee transaction and the cost?
…
Even assuming 0 traffic I’d like some idea of speed for a simple dapp. Like rock paper scissors…what’s the cost and speed? 5 seconds? 5min? .5 eng? 5eng?”
Yes to both.
After having run dozens, if not hundreds of integration tests in the same environment that has been made available on the developer testnet, I have observed that the simplest secret contract of a calculator (a+b or the like) takes about 1 sec, while the most complex contracts we have to date (which are not necessarily pushing the limits of complexity) take between 5 to 8 seconds to compute.
The current gas cost (in ENG) is the costing scheme that we have lined up to go to mainnet with, which we can certainly tweak and adjust, but should be in the same order of magnitude as the one in use on mainnet (pending feedback from the community 
)
Thanks Victor! I think this answer deserves to be added to the documentation FAQ I’ll add it soon!
What’s the example of a complex contract?
How does Enigma network computation cost compare to Ethereum gas cost in relative order of magnitude?
This is an example of a complex contract currently (please note that it is not only what you see in terms of code, but the linked libraries (crypto) that are brought in scope of the contract to add additional functionality). And in absolute terms this is not overly complex, this is just to contextualize my previous answer.
It is comparable on a 1:1 basis if you assume 1 ENG = 1 ETH (which I know it is not true on a real value). We took the Ethereum gas costing scheme from the Ethereum Virtual Machine (EVM), and used those base numbers with ENG. So in that regard is 1:1. Though then we added additional costs in terms of writing to the encrypted state, which is not present in Ethereum but is analogous to writing to the Ethereum state. @moria may be able to provide further insight.
Is it possible to pay in ETH as gas cost or is the gas cost requirement exclusively ENG only?
Gas cost in the Enigma network needs to be paid in ENG. However we are looking to ways in which we can abstract this for the user. The idea is that a user will be able to pay everything in ETH. In the background, we will work with a swap contract like Kyber. The swap contract will convert Enigma network fees to ENG and pay the workers
Shouldn’t add too much latency. We should be able to do everything in the same block (both the task receipt and the swap)