I own a couple Ibanez guitars, an RG 570, and an RG 470, both of which I bought used, for around $250 each. Mine seem to be pretty solid, well built and playable instruments. The RG 570 plays and feels every bit as good as my Jackson RR1 which cost considerably more, (though I bought that one new). The R5 470 is just noticeably inferior to the 570, but still not bad, certainly not a "pos", as herbman puts it. I suppose though that maybe mine aren't "low-end" RG series, but more "middle of the line" RG series.
And since I originally wrote this, I bought an Ibanez Prestige which totally kicks ass (despite its stupid name). And, I did see in a catalog, a low-end RG series... apparently the "RG" designation is being diluted, or perhaps it never meant what I thought, as this one did look like somewhat of a piece of shit, with a non-locking vibrato.