My first condenser was a rode nt1, the second an nt1a.
I have found both to be extremely versatile and deliver crisp and clean signals.
They are slightly different, but not so different to not get away with using them as a pair. I recorded a brass concert band using the two, and the results were beyond my expectations.
I tend to use nt5s for detailed work (e.g. drum overheads). What I like doing is recording guitar using the NT1a on the body and an nt5 up the neck.
I have a feeling that the nt1a has a bit more mid range than the nt1, and I use this when trying to match the mike to a vocal.
Curiously, I read on this forum somewhere that nt1s were made in China. This is not the case. My certainly bears 'made in australia' very proudly (as does the nt1a, of course). I understand that all rodes are australian-made.