Should I sell ETH or Hang onto it?

Short answer: Yes

Long answer: The current movement of ETH is purely the result of the demand and supply of the current time. Once we understand how it operates we can make inform decision. With so much ICO going on the ethereum platform there was huge demand for ETH. Demand drove the price up. So the price skyrocketed. Some of the ICO that were planned to go on for a full calendar month reached hard-cap on minutes to hours. Some didn't even go to ICO because pre-sale stage got them what they wanted?

So why is it going down? Setting a side the obvious fear of scalability of Ethereum network for a moment, Part of those ETH the ICO raised were meant to pay for developers and other costs. So those were needed to be 'sold' to a fiat currency so that the developer can pay for his/her bread and pay for rent etc. Up until those commodities are still bought and sold with Fiat currency alone, we will have to accept the ride will be this swingy however many of these ICO are meant to work toward solving that problem. So when there is a greater supply the price is going to go down and that's what's happening currently.

Scalability is a technical problem and out of all problems, technical problems are usually easiest to for the programmers to fix. There are enormous amount research actively looking at finding best way to solve these problems. So we have to hang on and sit tight that someone will find it. With this much of financial stake and brains behind the Ethereum, the odds of finding a reasonable solution is higher than not finding.

So dilema now for reasonable investors: Is it another tulip mania or there is actually some value to it?

Being from programming background, I can tell it is definitely not a tulip mania. There are real use cases with concrete financial incentives. Current price or present value may be off the chart but the same is true to Tesla shares or Google or Facebook for that matter.

There is also a fear of the whole industry not being regulated so the risk of losing everything to scams. That's true that's a risk but isn't that the whole foundation of 'decentralised ledger'? The Bitcoin came into foray to defy one central authority controlling all aspect of finance and manipulating it to benefit of it's selected few.

I wouldn't recommend anyone to buy or hold it in margin accounts but if you have some disposable dollars lying around, it's not gonna harm to buy a few and if you already have some ETH and tempting to offload it. Don't do it unless you really need that fiat money right now.

Disclaimer: These are opinions of the author and readers should not solely rely on author's assertion while making financial decisions. The author has stake ETH and other crypto currency and intend to hold it for longer period of time.