I miss being barebottom but like the look of a little sand better. FWIW I just added a third MP40W to my tank today and when money permits I will add a fourth. I know even with three I am getting lots of detritus build up in the sand. I have a Koralia 4 in there too, plus my return tank is 160 gal. The trick with BB is keeping the detritus out of the system. Either have flow set up so that you can syphon it out as it collects in a certain corner or have enough flow so none settles. WHen my 58 was up it had the return and 2 MP40W's and a little still settled. My skimmer would process it out in the sump and if the sump ever got a build up I run a sock for a day and get it all out. Running my tank that way, along with the prodibio and w/c's my tank was overly clean to the point it allowed me to overfeed my fish, which I like.
I still think a tank with clean sand looks better then one with a BB and a faux bed would just get covered in coralline so I don't think thats a good alternative. Its all preference I guess. I thought I wanted sand in my new tank but long for the ease of keeping the water cleaner. I havent decided yet so for now I am keeping my sand in, who knows.