All these programs JL_Cmdr, CrackUtil, BBSAK, MCP all use the RIM program javaloader.exe (the link in the OP's post actually refers to javaloader) as their engine. All the other function of these programs are just an interface and clever options built around javaloader.
Provided the UI of MCP issues the correct commands to javaloader then this is a good program. I did not check to see what else has been implemented but I remember that the author seemed to have a lot of good ideas and the ability to carry them out.
Would I use this program. No, not till someone else has tried it out and reported back here.