There is an aspect of the Dark side that makes you a slave to your emotions and passions, while the Jedi simply choose to be slaves to the Force.
The Sith allow for a far wider exploration of the mysteries of the force, but still emphasise on mastering the Dark side and little else. The Jedi on the other hand have a strict rule on not even contemplating the dark side, but support the full spectrum of uses for the Force in any other way.
Finally, the amount of Jedi that have actually left/ been expelled from the Jedi order can apparently be counted on two hands, While the amount of Sith killed by backstabbing fellow sith is certainly more than 50% (90% with the rule of two, as each disciple would murder their master once they had outlived their usefulness).
Personally, I think my chances of survival and emotional/social/economic support would be much better with the Jedi. Plus, I believe there would be no stopping me if I decided to leave once i achieved an adequate level of mastery in the force.
I'd probably run off to become a Mandalorian XD!