The main objection I have with magazine disconnects is that the pistol will not fire IF THE MAGAZINE IS NOT FULLY SEATED!!! There have been incidents where this has happened, either because the mag wasn't inserted with enough force, or the release button was bumped sometime after the magazine was inserted. Some badly designed and/or modified holsters will do this.

In the early days of the Model 39, two cops on an eastern police department were shot while trying to shoot back at their antagonist but their -39's failed to fire because their mags were slightly unseated. Investigation showed their issued holsters likely bumped the release buttons. S&W settled the resulting lawsuits out of court and then doubled the strength of the mag release catch spring to make a repeat of this less likely.

All that said, pick a pistol that has the design characteristics you like and place value upon. What may be a desirable feature in one circumstance may be disadvantageous in another.

If I decided to carry a S&W pistol so equipped, I don't think I would worry much about it. The system they have is now pretty reliable.