Even I agree... humbly besmirching my beloved MDF. The thing I like about MDF is it's thickness consistency... even for crappy Chinese made. I can focus my laser in seconds by lifting the bed to 52.45mm for 6mm MDF and 49.69mm for 3mm. However, if I sold them, then the effort may be worth it, but as for free give aways, the MDF is quick and hassle free. If I costed time for selling, it'd be several hundred dollars... the hours spent recutting, glueing breaks, filling... and then going back to recutting, glueing breaks, filling... recutting, glueing breaks, filling... recutting, glueing breaks, filling... Several times the box crumbled while holding it finger tight for the CA to set.
If your first cut is too short... Take the second cut from the longer end... LBD