I am using Grant Thornton, started IVA process with first phone call at the begining of February, have only just received my proposal. To this date it has taken 16 weeks, I thought my case was straight forward and have returned all paperwork within days of asking. I was also told originaly it would take 4-6 weeks. I think they are very very busy at the moment and things are taking a lot longer than the time scales they set out. The 14 day wait for the proposal took 7 weeks. I have heard very good things about GT from this site and they do seem to have a good sucess rate, but do check your proposal very carefully, mine had several big mistakes, wrong name, duplicated debts, some debts £3000 out, and my income was wrong and the expenditure bore little resemblence to that discussed in the initial phone call. It may have been inaccurate as they are very busy and I have been pushing them for my proposal for weeks. Mine may just be a one off, wish you all the best with your proposal.