Really depends on what you want to get out of it..
- BTS is the core tokens and should rise in value as the adoption of the platform increases
- HERO is a smartcoin pegged to the USD (w/ 5% p/a interest/growth) so will give you value stability
- OBITS is the native token of OpenLedger and has some interesting opportunities
Beside those options there are many other tokens on the platform that all have their own value proposition