I always have something to play over before I record an external source. Usually drums and a keys. So I'd have a bus reverb set up. When I just play and want to hear it through a reverb, I'd use just the track.
 
I tend to use 2 bus reverbs, so they are in parallel. On a track this would have to be in series, so the reverb 1 is going through reverb 2, which I don't want. 
 
Bus reverbs for the mix
Track reverbs when you want it to sound a little different of someting special to the rest of the mix. I don't record vocal, but I guess this would be a good situation for having something unique going on.

This has been beat to death.  But, My MOTU 896mk3 Hybrid has a reverb option for the singer (or whoever) and it is not sent to the DAW.  Thus the singer can hear reverb but the recorded track is dry.  I've had other recording interface units before the MOTU and they all had the "local" reverb option.  Didn't have to do any tricks in Sonar.

Sanderxpander
Do you really set up different pre-delay and tail EQs for different vocals during tracking??

Not really to be honest, just different presets I've created over the years.
The only real difference I've noticed is by using the same reverb for multiple tracks, your feeding the same Reverb with multiple vocals. and im not sure if you have ever noticed it, but when sending multiple signals through the same reverb all together at once, it can sound a bit like mush. Having independent reverbs just sounds cleaner to me.
No ? The difference is slight but it is there.
I could probably do the same as you. the only difference is I would be deleting Sends instead of FX bin reverb

I have the exact opposite experience - using multiple reverbs (especially with different presets) makes for more mush than using a single one.

I once again continue to learn as I read the various discussion - this discussion has been helpful...

Watched a Youtube video with a slightly nauseating Fab Dupont, he used three reverbs. The first he called the office, which gave presence. The second to create the space, so a Room, and the third a plate to wash things together. I liked the idea for both using layers of reverb to add touches of each and get an individual sound to sit a certain way, but also to plce sound within the depth of each to create clarity.
 
I had just been using one, but I shifted to two, the Room and Plate (for example) But since buying samplemodeling brass, which is dry, and can be bone dry with the early reflections turned off. I thought about just switching them off and add that office fro the same role.   

Sanderxpander
I have the exact opposite experience - using multiple reverbs (especially with different presets) makes for more mush than using a single one.

Think about this,
Vocal one is singing one part, routing part of that signal to a send to a reverb bus.
Vocal two is singing an over laying vocal / an offset (Totally different rhythmic line). that reverb has to process two separate vocal parts doing two different things.
 
I use sends no doubt, but its typically in the mix down process and more often than not, there are never two or more instruments/vocals feeding that send bus UNLESS they are doing the same exact thing.
 
We all work differently. there's nothing wrong with that. I can see your point and respect that.
I hope you can do the same. If you cant, oh well. its only an option. Im not going to be mixing any of your projects anytime soon and you wont be mixing any of mine

Of course, everyone has their own workflow :)
Always interesting to read about someone else's process.

Going back to the basics of what reverb is though, of course a reverb has to "do" two things if it has to process two vocal lines (even though the audiostream is blended before they hit the processing), but that's no different from two singers standing in the same room singing two different lines. I personally prefer that to putting them in different rooms singing two different lines. The latter will create unique reflections for each, true, but also a generally wider and thicker spectrum when you sum the two reverbs.

Anyway, if you have a way that works for you and your results are satisfying then don't let my opinion turn you off :)

whenever I track with reverb in sonar, I do all of the above... only... make sure that the reverb plug in in your reverb track is set 100% wet.  Many reverbs default to a 40/60 mix...etc.    The echo your getting is not reverb, its a dry repeat coming from somewhere.  You don't need an external unit.    Get the dry zero latency from your interface and the wet repeat from sonar.  You wont notice latency with just wet reverb etc.

Great discussion, food for thought. Different strokes I guess.
But we are getting a bit "off topic" (not a bad thing).
Interesting; 10 posts by the OP, all in this thread, and off we go .
Maybe the OP will post his specs and we can get him laying down his tracks with confidence...
But remember, he wants to "hear" a little verb while tracking; not print that verb.
T