Per Vic's comment, it's a pretty 'risk free' decision, since they are identical size and easy to swap out. I guess I would say that I find the extra mid presence and slightly lower treble frequency range of the Sadowksy single coil pickups REALLY sound good in the ash/maple models. I've A/B'd so many MV5's (60's position) and Metro UV 5's (70's position) that I've come to the conclusion that the slight difference in 70's pickup position is minor and subtle... I wouldn't get hung up on that.
Interestingly, I disliked the HC's enough in the ash/maple models that I decided to swap out the HC's in my RV with SC's (Sadowsky). I always really liked the way my RV sounded with the stock HC's, but thought 'well, if the SC's made the MV sound so good, maybe it will make the RV sound even better'. WRONG! I'm putting the HC's back in. That softening of the upper treble, the bump in the mids and the slightly tightening of the low end that the SC's give you versus the HC's (which are a touch scooped, deep and sizzly up top) really 'improve' the MV ash/maple models to my ear. However, the RV's (IMO) actually benefit from the wider, more pure tone of HC's. The singles made my RV growl a touch more in the low mids, but it really darkened the tone of that bass and resulted in a low end that is too thin for my taste (my RV is very lightweight and routed, my MV is non-routed and heavier).
So, IMO it's not just as simple as 'put SC's in and be happy'. All this stuff interacts with each other.
That being said, I could die a happy man playing a Metro UV70 with single coils
Just FYI and IMO and IME!