Pound-for-pound (depending on the deal you get, of course) the budget ESPs seem to a bit be better than the equivalent Jacksons. It could just be down to the way the examples I've played had been set up, of course...
Agreed that the Ibanez guitars are really good esp the RG series. I have a Jackson ATX and upgraded the bridge pick up to a Dimarzio FRED and now sounds the business. And that was a £1000 guitar when I bought it in 1999.