I currently have the Jumbo Shrimp and have been around Modwright stuff.
Both products have fairly different presentations. If you seek more of a modern type of sound, the Modwright would be the way to go. The Manley is richer, and more of a flesh on the bones kind of sound. That came as a bit of a surprise to me, as it's different than their typical amplifier. Then again, I would think they would balance one another, and prove complementary.
Only you can decided which sound better suits you.