Are the AIR-AP1242G-A-K9 upgradable to AIR-LAP1242G-A-K9.
What about the AIR-AP1242AG-A-K9 ?.
WLC is a MUCH cleaner solution than WLSE. I don't think I've deployed a WLSE in the last 18months now - everything is going lightweight. Even old WLSE's can be upgraded to run WCS, so no real excuses about loss of investment either.
You can swap IOS / LWAPP images as you like, so no worries about trialing LWAPP, and then reverting to IOS again if they don't like it.
IOS APs can be migrated to LWAPP using the "LWAPP Upgrade Tool" (free off CCO), and similarly, an LWAPP AP that's registered to a WLC can be converted back to IOS via a CLI command on the WLC.