You need to consider that about 95% of all self defense shoots, even officer involved shoots are over and done with 5 rounds or less, fired at 5 yards or less in 5 seconds or less.
In fact, the FBI looked at 12 years of agent involved shoots and found that 75% involved 3 rounds or less at 3 yards or less.
Reloads are just not a factor in the vast majority of self defense shoots.
I'm not sure where you're working or your office policies, but my guess is that as a probation officer, you are not going to go into known hot situations, make calls in known hot areas, or go out to arrest a violator without a officer along to back you up.
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With that said, my preference is to carry a Model 66 or a Model 686+ as the K and L frame revolvers are much more effective shooters and the ballistics are better with a 2.5" or 3" barrel in either .38 +P or .357 Magnum loads.
They are a bot heavier, but in a good IWB holster they are not really any less comfortable to carry all day long and not much less concealable.
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Either way, a speed loader is still nice to have, and is much faster than a speed strip, but for concealment purposes you'll want to carry it in a slip over hold that slips over the belt and gives it a lower profile.
