I used to use an acid stop bath for film. If you contain it in a bottle and pour directly into the tank and back into a bottle then even the acetic acid stop shouldn't smell too harsh but if it does then the "odourless" citric acid stop can be used.

I have since moved on to water and haven't seen any difference in the negs. If you fill the tank with water,agitate and pour out quickly several times then this seems to overcome any tendency for the dev to continue acting as the remnants of dev is diluted greatly on the first wash and must be virtually non existent by the second wash. If someone with as much experience as Roger Hicks believes that over most development times an extra 15 secs in neither here nor there then the extra dev action accounted for by an extremely diluted dev which is almost all water even on the first rinse suggests that maybe the dangers of not using an acid stop to stop development is very overrated.

Incidentally what does Sprint use which hides/avoids the normal and familiar acidic/vinegar smell? Is it a different substance from the usual acid or simply a strong masking agent to counteract the normal smell?

For paper I have retained the acid stop but I don't think your question was aimed at paper processing.