If you are looking for more of a seamless wireless infrastructure then you want to stay with the enterprise device. AP541N clustering is exactly what it means in the admin guide.
Administration guide PG: 139
The Cisco AP 541N supports access point clusters. A cluster provides a single
point of administration and lets you view, deploy, configure, and secure the
wireless network as a single entity rather than a series of separate wireless
What clustering gives you: whichever AP541 access point you log into and make changes too, then it will replicate those chances to the other AP541N; still acting as individual AP within a network. So if your customer wants a wireless roaming network then the best decision would be your initial setup implementation suggestion.
In the administration guide it does talk about roaming clients; which of course is different than wireless roaming. Roaming clients are clients moving around within a wireless topology.
Hope this helps,