I'm playing at a Boosey&Hawkes Imperial, Large shank, Serial No. somewhere about 54**** (1974). It's a beautiful horn, nice sound, good high and very good low range, and good mechanics. It's also a heavy euph compared to the YEP-321. I've ordered some spare parts by Dawkes music and now the valve action is quiet, too. I [EDIT:] don't see currently need for upgrading to a modern euph. The SM4X works great for me.
I would say, thumbs up
Last edited by JoCologne; 01-17-2014 at 03:01 AM.
Jochen
Boosey&Hawkes Imperial with SM4(U-X),
YEP-321 with DW 4AY ...
... and my cello