Depends on the strength of the covenant, as anywhere.
Return of just under 6% is about right for Glasgow, but there are a few obvious things to watch.
Strength of covenant. Who are the tenants, and how solid are they?
Are there break clauses, and when do they occur?
What is the likelihood that the tenant will avail of the break? Are they growing and likely to need a bigger place for instance, or are they shrinking?
If they look liked they are staying, what does the lease say about revisions to the rent? Are these revisions upwards only?
If the premises are retail, is trade on the decline in the area? Don't forget that the big shopping centres are sucking the life out of the high streets there (a bit like here really).
Also remember that there are several types of commercial zoning in the UK, and it may not be easy to change from one to another. Changing back to residential, apartments, etc will almost certainly not be allowed by the planners, and they are very sticky on this.