Though they sound great theoratically,"tap dancing live"( to pressing 2 switches all the time with your feet-to input single finger chord like info) may not be that practical if you want to focus on playing guitar/singing;though you can use as a simple drum machine -(intro-vari1-fill1-vari2,3-fill2-ending etc).
I would check GEM xp module out (more tuned for arranger live use with a midi controller,but havier)before getting MIDJAY.
but getting a T1/T2(or lighter 3K)is also advised for the long run(for super fast song creation-excellent 3rd party support for styles,kar /xg files with vocal harmony).
Did you check your mail,Asim?