Time to retrieve data and convert to ARL

[ogersentia]

Hello,
I would have liked to get reanalyses data over a decade or more to make a climatological study from hysplit outputs. However, testing to download only 1 day ERA5 data and convert it to ARL took me more than 24h ... Is this realistic?
So I am wondering of the feasibility of what I aimed to do. Should I take GDAS data although I will loose meteorological accuracy? What do you thing?
Best regards,
Sentia Oger