Hi there,
I did both my CPL and IR part time whilst working the rest of the week. I used to work tuesday, wednesday and thursday at my company, then fly friday, saturday and sunday. Only having mondays off was tiring and would have been even more so if i had family or other commitments. Would definately recommend atleast one day off a week otherwise you might burn out. I also feel that you need time off to reflect on what you have learnt.
I needed an extra 1.2 hours before my IR test and passed first time. Dont think doing it part time made any difference to me passing first time or needing the extra 1.2 hours. Seemed most people needed atleast that whether they did it part time or full time.
Best of luck!