Reading is faster - a reason not to do it! There’s a reason that rituals across time and space have had readings from time immemorial- and not just because of the cost of printing.
Especially with a work like LotR it can be very tempting to skim parts; the audiobook will just continue on, which can help you encounter passages you’d normally have skipped over.
Absolutely! I'd read LotR many times before I first read it aloud as a bedtime story season and was abashed to find how much I'd been skipping over, mostly parenthetical details of geography and world-building, while hastening in pursuit of the plot, like the holder of a big box of bonbons gorging target than savouring.
Especially with a work like LotR it can be very tempting to skim parts; the audiobook will just continue on, which can help you encounter passages you’d normally have skipped over.