Right now the Zenpool is paying out 0.00065
BTC/Mh which is twice as high as a payout per MH as other multipools such as clevermining.com. If you only buy 1 MH then your going to have to wait a few days to withdrawal because the network fee that they force you to pay is 0.0002
BTC, which is essentially 30% of a single mining day.
If you're going to buy some hashlet power you should
check out some of the discounts that I
listed in this thread to at least save yourself some money.
Also since we don't know the long term outcome of being able to supposedly mine scrypt coins faster than any other multipool out there, I'd suggest not investing too heavily in these miners. However, with that being said the 1MH/s miner currently would only take 46 days to have an ROI of >100% so maybe start small and as they pay themselves off, re-invest the earnings to make more BTC per day and build it up from there.
I wish they were more open on the payout. I like their numbers alot per mh on pay, but I just don't see what they are doing to get this.
The biggest thing I don't like compared to other miners is that you really don't have physical hardware you can convert to. I would like it a lot better if I could buy a hashlet and at end it is my hardware since this is a long term deal. But guess we will see in a few months or so. I might be kicking myself if everyone get's great ROI on this. As of right now I'm still watching the next gen ASICs to see what happens(and it seems to be slow).