From my own personal experience, a standard EZ-Flash Omega works well. You're welcome to spend more on the Definitive Edition or an Everdrive, but for $50-$60 and a slight learning curve I have no complaints with the standard Omega. Just wait a few moments after saving before shutting the power down and back up your saves on a regular basis.
Goomba Color (and my fork, Jagoomba) works fairly well for running GB/GBC games, but if you want perfect compatibility you may want to consider a GBC flash cart. Some games don't work in Goomba and I am slow in fixing bugs in my fork.