The house edge when you bet on 2x is 2.5%, and as you increase to 10x the house edge goes down to 0.5%. So obviously with the higher multiplier you have better odds.
This is not accurate. The house edge on FreeBitco.in is 5%. Regardless of what multiplier you are using you are always expected to lose 5 Bitcoin for every 100 Bitcoin that you have wagered.
You're correct. Sorry for the misinformation. Please ignore what I posted above.