Currently Ethereum Monopolises the market. Lisk isn't released yet so it's unfair to compare the two platforms. I think regardless of current technology, Lisk will start an arms face leading to better and faster development of both platforms.

Lisk is unpredictable, like all cryptocurrency. It's not a venture capitalist market where you can send your team to inspect the company. This is true for Ethereum as well.

As we all know, only put it what you can afford.

Try not to ride the hype train. When you invest in a crypto, please read the white paper, read up on all the staff (Lisk staff have a very public profile) and evaluate the real world value of the system.

In disclosure I invested 50 BTC into Ethereum in ICO, and 60 BTC in Lisk because I think, regardless of release date, the technology is EASILY worth more than 5.9million.