No, not talking about MCX (24" bikes). The M500 and some other 26" models were produced in Killer-V type frame configuration in 14" frame size (XS). Other MX00-series models did not offer 14" (XS) frame at all, but sizes started from 16" frame (S). Went through catalogs, and it seems that at least for the year 1996 the XS size M500 in KV frame layout did not spec: 2,5" downtube (2" instead) and butted seat tube (normal instead). So there are internal differences between these same looking frames.