If your Gen1 is in good shape it is worth keeping.

The Gen2 adds three features and has planned firmware support / updates (I think the Gen1 is done as far as firmware R&D)

1 - you can run a high voltage setting for the BEC on the Gen2
2 - you do have data logging on the Gen2
3 - you have the data port which is handy at times on the Gen2

If your goal is to run a HV servo for more speed and torque it may be worth ditching a perfectly good Gen1 for a Gen2. Other than that they compete very well against each other in my opinion.