Scanning over the Super 60 list... it strikes me that almost ALL the OEICs are Acc units. The one exception is "RGI UK Recovery B Inc"... and looking at trustnet the only other unit class of that is "RGI UK Recovery Z Acc" (considerably cheaper OCF on the Z units, but doesn't seem to be available on ii; maybe they don't have the AUM to qualify for that class yet).
Artemis Monthly Distribution (Inc units) is our largest unsheltered holding. Pretty happy with it and I don't know any reason the Inc units would be considered defective/inferior to the Acc ones.
Maybe it's just that someone at ii/Morningstar decided that the sort of investors using Super 60 are better served buying Acc units (compounding!) than having to be more hands on with divi reinvestment. OTOH that Artemis Monthly Distribution fund does sit in the Super 60's "income" subgroup, so you'd think they'd lean to Inc distributing units at least for those.