Wee Hugh,
The thing about microfilm is that it is robust. Some of the tapes at PRONI are 65 years old now (I am thinking of the Registry of Deeds tapes) and they are still in pretty good condition. One of the PRONI managers told me that apart from the cost implications, there’s a reluctance to transfer the data they hold on microfilm to any other format in case it becomes obsolete as floppy disks etc did. Their thinking is to spend money on acquiring new records and protecting existing records but digitizing the microfilm holding isn’t on the agenda. (And they have just had their budget cut). So I think the microfilms are there for the foreseeable future.
Watch out for the NI National Register records (ie the September 1939 mini census, compiled for ration book provision etc). PRONI are going to release these records (subject to restrictions relating to people still alive) in a few months time. My spy tells me they will be free to search (in contrast to the £42 fee payable for similar searches of the records for England & Wales).
I think that’s a poor show regarding your bicycle. I’d be inclined to raise that with them and ask them how the lack of provision for bikes sits with Government targets on green activities, getting people to use sustainable methods of transport etc.