I will clarify up front that my cruising experience amounts to one cruise. A year ago we cruised on Oceania in the Mediterranean. I use a wheelchair full time, 100%. I was told up front that the wheelchair couldn't be wider then 22 inches, though many phone calls and emails through my TA and Oceania couldn't give me a reason for that. To be safe, I made a series of modifications to my 27" wide wheelchair to get it down to 22.5". We figured out the first day of our cruise that 22" is how much clearance is left in the corridor when a housekeeping or room service cart is parked there, which they usually are. I could just squeeze by. I don't know if Regent corridors and carts are the same dimensions but if they are, relying on a wheelchair that doesn't fit by them would be a huge hassle. The staff using the carts may not be nearby.