Not being a horn player, I have no direct knowledge of this. However, in the community band I play in, my section mate is the mother of a 16 year old high school student, and a few years ago she got her daughter a horn from Mack Brass. The daughter has been playing it in school band, and also in community band. They're both thrilled with the instrument. The mother is an excellent tuba player herself and takes music very seriously. I'm sure the Wessex horns are in the same range in terms of performance, but they are considerably more expensive and Mack Brass offers three different models (http://www.mackbrass.com/).
Gary Merrill
Wessex EEb Bass tuba (DW 3XL or 2XL)
Mack Brass Compensating Euph (DE N106, Euph J, J9 euph)
Amati Oval Euph (DE 104, Euph J, J6 euph)
1924 Buescher 3-valve Eb tuba (with std US receiver), Kelly 25
Schiller American Heritage 7B clone bass trombone (DE LB K/K10/112/14 Lexan, Brass Ark MV50R)
1947 Olds "Standard" trombone (Olds #3)