Dont concern yourself with the power ratings too much (especially not peak power). People run way more power than rated all the time. As far as all around loudness, theoretically, the A series 6x9 and the D series, given the same amount of power will be equally loud to the ear. The main difference will be the sound quality/clarity (I can personally attest to the fact that the sound difference is pretty noticeable from the A to D series Pioneers) . Also, personally, I prefer 2 way coaxials to 3 ways because that way your power is only split between 2 drivers as opposed to 3. That extra tweeter on that 3 way wont make it any louder. Dont worry about the range either I know for a fact those Bostons will play lower than the specs say; but, you'll probably want to have them high passed to keep the bass out of them anyway since you will have subs.the pioneers hadndle the same rms as the one i said on here, they handle a bit more peak power tho...im guessing the material would make em sound cleaner tho, but do they sound louder than the ones i said? they are 2 way and the others are 3way....and the boston acoustics only handle 35 rms would they sound less loud than the pioneers i said or the ones you just told me? their range is less than the pioneers too.