FTL Warp Factors.. a question..

 I'm wondering if..

0.10c is 'Warp 1'
0.20c is 'Warp 2'
etc
0.90c is 'Warp 9'

OR

1c is 'Warp 1'
2c is 'Warp 2'

It's most likely the first one.. because the second one is time travel.

I read that Helium-3 won't make a good fuel for FTL.. but I don't understand why.

While Matter-Antimatter IS better and I don't deny it.. He3 could be used as fuel via Ion drives, pushing electrons out. It would mean we could send probes to Alpha Centuri system.. the system is a tri-star system.. and we could visit each one and send photos back.

Slowing Down..

Reaching 'Warp 5' or 0.5c makes it so the probe would arrive within 10 years. But slowing down would inhibit travel to the other stars..

Instead why not drop a secondary smaller probe to an Lagrange point of one of the exo-planets? And do the same again for each star?

Just a few thoughts there..