Sounds good on that tool!, I didn't see that detail in the product photo. If ours fizzle out we'll order some. We use real null meters because we have them and much less added noise and quicker to use, but a 3548a / 56a can work also as you have it set up. Yes, good advice to always keep reversing the leads (then difference divide by 2) no matter what "null meter" you use to compensate for whatever other errors in the system. That's how it's done.
We don't normally adjust 732's either, just send them to Fluke for Calibration as "Measure Only - Functional Test" and they haven't had adjustment in years - and we know exactly what they are for voltage. Probably don't need adjusting anyway if they are cared for, but you do want that drift record - if you see that start to change that can be a head's up that a unit is starting to drift. The only time we'd do an adjust locally is if we're fixing up a new old unit that needs to go into to service - you can't have too many in the cal rotation. But it's good to do a local adjustment first before sending an "unknown history" unit to Fluke so they don't get worried that it's too far out.