MESA 12AX7A Tubes in Bugera 333XL 212 Combo

[Muskratt]

I have a few brand new MESA 12AX7A tubes (STR-12 AX7-A) that I was wondering if I replaced the two specific factory A-tubes if I would yield a better tone or gain with these MESA's?

Has anyone tried this yet? or does anyone know how these MESA tubes sound against other brands to get a idea?
Does anyone know what specific tubes are the 12AX7A's in the 333XL Combo.
And Last if I change these I take it no re-biasing is needed being the Pre-stage.

Thanks.

[Jazz P Bass]

My guess is the Bugera tubes are "picked" for being nonmicrophonic.
Like the old 7025 tubes.
No, you do not need to rebias.
Swap away.
You'll know if it is better or worse.

[Ramsay]

The 12AX7 Mesa Tubes are selectioned, nothing more.
They will work at your Bugera 333XL with no more quality than a 12AX7 JJ simple that.
You not will see diference in the sound!!

[Muskratt]

Thanks for your replies. I had tried the Mesa tube in the rig but I could NOT hear any differences what so ever. I don't have any other 12AX7B tubes so it was pointless to continue.
I decided to switch it back to the Bugera Prem tube to try and live out its life in harmony.

A trick I found getting those tubes out was a piece of the non slip rubber you put in your cabinets. It light and flexible and grabs glass when you can get much grip.. Just don't try it on hot tubes.

Thx Guys.. I really would like to get the EuRo Tubs KT77 gold pins set for this 333xl down the road.