Doesn't look a bad deal to me, as it works out at around £4.79 per film and the latest one is included here too. Was previously posted here at £39.99!
Thanks to AcornGuy2012 for pointing this out, you may get this even cheaper through Flubit.
This product contains:
Muppets Most Wanted
The Muppets (2011)
The Muppets Movie (1979) [New to Blu-ray]
The Great Muppet Caper [New to Blu-ray]
The Muppet Christmas Carol [New to Blu-ray]
Muppet Treasure Island [New to Blu-ray]