Have you looked at ihostmn.com service? They have now passed GTM when it come to the number of nodes hosted. They also have a shared MN service.
I wrote previously that masternode hosting industry seems to go to collapse, not only GINcoin (that did scam exit) or Gentarium, or any other masternode hosting platforms. Shared masternodes is the most terrible ideas I think. I don't support ideas to join and let your money in shared masternodes (on Gincoin, Gentarium, ihostmn.com, or whatever sites). That is risky.