A John Packer or Wessex?

[Wyvern]

I heard mention of Wessex venting valves standard

The latest Wessex Dolce all have vented valves. They are also now finished using a new mechanical polishing process, so the finish is superb.

[Wyvern]

Tom McGrady has the Jinbao for $995.
http://www.mackbrass.com/Euphoniums.html
If gold trim and four holes in the valves are worth $450, you should probably buy the one you've been looking at.
You seem to be strongly leaning towards Jinbao.

That is not the same euphonium as the Wessex Dolce. We have made more than a dozen improvements including hardened bell of heavier gauge metal, new floating leadpipe of gold brass, extra strengthing plates of nickel, 2nd valve water key, tweaks to tuning, vented valves, nice tactile engraved valve buttons and thicker silver-plating. Plus guaranteed by our quality checking and manufactured by the most skilled technicians at factory.

[Mandalf]

Have you played any new euphoniums, or only looked at pictures on your screen?

Yeah, I've played on a few. Yamaha YEP-321, YEP-201, Meinl Weston 751 Phoenix series, Adams E1, Besson New Standard (an older model from '66), a couple of the lower Tuba Exchange models, most of the Eastman line up, and a Jupiter 1120S.