The Bulwark team does not support or endorse any shared masternode or staking groups. They pose too large of a risk to the userbase for us to ever recommend anyone take part in them.
Anyone thinking of shared masternode services should understand that they are essentially forfeiting any 'right' to 'their' coins.
You are sending your coins to a third party, who promises to use your coins and others to run a masternode, but with no recourse if something goes wrong. Now some of these services may be more reputable than others, but you are wearing 100 percent of the risk and sharing in any gain.
Up to you, but with the bulwark team's warning as well just think twice before hitting send.