Just seems like you're looking for validation not to get an i5 in all honesty (Which isn't a problem, it's just a little strange, given that the comparisons aren't comparisons)
If Steamroller's good, AMD are going to charge for it, as always, AMD history is blessed with ignorance, check Bulldozers launch pricing when AMD thought they had it nailed
Steamroller's upto 6 months off, being in a similar situation before, I'd just jump at what I could/wanted now.
If your budget is around 500 quid, then look at an FX6300 with a 7870 or something.
I'd personally much sooner go second hand i5 than buy an FX, but that's because I generally have the easy option to do so as I support a few gaming rigs, so I can swap parts around and get the best performance for the price I can.