Hadn't considered that! Since isotropic went down I've only been playing real life games of Dominion.
Good one, though.
I realised I forgot to say why my game I felt 5/2 wasn't as good.
I was the first player, and I had 5/2, he was second player with 2/5.
Cards included Torturer, Lighthouse, Witch, IGG, Moat, Hamlet, Watchtower.
I went IGG / Lighthouse. He went Hamlet / IGG.
My argument here was that when I played my 5 he already knew I hadn't got a torturer or witch, so there was no need for him to buy a Lighthouse. In contrast, I had to play my $2 without knowledge of which $5 option he was going to go for, so I felt I should buy a Lighthouse anyway.
Arguably Witch was a better choice anyway, of course...