Best tubes for the Exemplar players

I've just gotten a Exemplar 2900 and wondered whether anyone ot there has had a chance to try various different tubes with it. I know my models previous owner had Amperex fitted, but are there any others worth trying?

Amperex E180CC Pinch Waist, GE 5965, Mullard E180CC, 7062, CEI 180CC. Email if you need some.
Thanks Smilin, are all basically good in their own right, with each offering its own interpretation, or does one stand out as being better than the rest?
I like the E180CC's/7062's best. The PW is the most musical, maybe a touch microphonic, but gives the extension without rolling off the frequency extremes. They are the most costly, at 150/pair. Close 2nd is the mullard/cei/amperex IMO. It really depends on your system, and personnal likes. I am not impressed with the 5965's, I was mistaken on the GE reco, I would have to check which tube that is, the 5965's pretty much suck IMO.

30 bucks for the mullards/cei which I believe are also mullards are the cheapest best to me.