i have a great budget LDC - the m-audio sputnik tube mic. having it be the best mic i've purchased yet means that i dont have any other $700 mics to compare it to, and it beats out even my best other mics (beta87, md421) 95% of the work i do is live (although, when doing live work i typically record via Mackie onyx / PreSonus StudioLive boards), so i dont think i'm using my Sputnik as much as i should or could. when i do use the sputnik, it would be for vocals or perhaps acoustic instruments. i think i want to sell the sputnik and get a LDD like the RE20, SM7b, another md421, etc. my reasoning is that i'd be able to use a LDD on stage and in studio sessions, and i'd be much more likely to use it. after all, that's why a person purchases something. another thing to consider is that i operate a mobile studio, and not all recording environments are treated properly; the sputnik picks up all sorts of sound reflections and room noise. although the tone is above satisfactory in the right room, it's not something to count on. SO... my fist thought was RE20 - i've read a lot of great things about it. i talked about it at work with a friend and he suggested the SM7b would be a nicer option. and finally, i've used the MD421 on vocals and really really liked it - but is it really appropriate for a live performance vocal mic? obviously it could be, but is it practical? tell me all your thoughts on this subject, and thanks.