I'm not sure I agree with the idea that 15's are unfashionable per se. OK, 15s are seen less often on stages and are easy to buy cheap etc, but that's true of all big cabs these days, 4x10/6x10/8x10 all fall into 'unfashionable', but this is a cabinet size thing, not a sound thing, we're simply all getting used to smaller boxes, so it's big cabs, not 15s per se, that are unfashionable. Certainly, that modern 10s and 12s are far better able to deal with the sonic territory that used to be the sole reserve of 15s is reasonable grounds for saying that bassists don't need 15s in the way they perhaps used to, but not necessarily for saying that there's something wrong with 15s per se as is suggested in one post above (there are good 15s and less good 15s of course). They still very much have their place if you have the space and like the sound. And the Compact is a very good example - I was tempted by the one above as I fancied a 2xCompact rig but that's more a want thing than a need thing, no-one needs a 2xCompact rig unless they're playing stadiums!