Sleeping pad/Tent Taj Mahal

[WildBoose]

I'm looking at a Hillebeg Niak (47in wide) and putting a 40in wide sleeping pad inside it (Big Agnes Rapids SL). Any foreseen issues with a pad that is almost as wide as the complete interior of the tent?
p.s....Im not overly concerned with weight. I'll take comfort vs. small amount more weight.