I have used both 35S and DIG for ISHH. I far prefer DIG and will never,
ever use 35S again. DIG is easier, safer, faster (results in hours rather
than days or weeks you get good spatial localisation and, best
of all, you avoid all that nasty paperwork associated with keeping track
of your radioactive waste. Boehringer Mannheim have very helpful manuals
for using DIG in ISHH. Good luck.