Reed Muse 3C turntable

Ok; I'll switch it back to the idler and comment on this thread.  I too bought it for the idler so I hope that the many other changes I've made since the switch to the belt make a big improvement to the sound with the idler.  I once read a short review where a group of about a dozen Europeans listened to the table and all but two preferred the idler over the belt.

I switched back to the idler/friction drive last night.
I immediately noticed that the bass tightened up and there was better definition in the bottom end.  I could more easily follow bass lines.  Because the bass was less dominant and bloated, more information from other frequencies came through.  It was as if the soundfield was 'cleaned' and each image had more room to breathe.  Pitch definition and was much better - especially noticeable on piano.  All of these improvements led to a much more natural sense of space and timing.  
So, was anything lost by going away from the belt?  Well, the belt is more 'romantic' sounding.  The pace is more languid and notes hang around and take longer to decay.  The midrange is warmer and the overall soundscape is darker.  With the idler everything is simply more there and matter-of-fact -- there is less editorializing.  
It's nice to have the choice between the two but for now I'll be going back to the idler wheels.
Why did I prefer the belt to the idler before but now I prefer the idler to the belt?  Who the hell knows in this crazy hobby.

At its best, DD is the happy medium .

I've found out why the idler wheels sound so much better this time than they did the first time I had them in: they were in the wrong position the first time.  The two wheels are of slightly different diameters and the big one has to go on the left motor.

I’m very happy with the 12v battery that I’m using as a power supply but I do find that the speed fluctuates when the battery gets very low (after 6 hours of listening). I intend on buying a bigger battery (more amp hours) but I’m wondering if there are other parameters that I should be looking at when selecting a battery. Ideally the battery would deliver a high quality 12v at any point in its discharge cycle. Perhaps there is a battery brand that is the gold standard in terms of consistent power delivery?