12ax7 vs 5751


hi all,
i need some advice. i`m very new to tube amplifiers and i`ve been doing some tube rolling.

i currently have a pair of grant fidelity matched psvane 12ax7t`s in my amp which sound fantastic.

what i`d like to know is which are the better tubes, 12ax7`s or 5751 tubes. i`ve been looking at forums and there are folk out there that say 5751 tubes are better than 12ax7 tubes.

can i have your thoughts on this please and also which are the good 5751`s to go for.

i really like the psvanes but if they can be bettered i`d go for it as my next line up of replacement tubes.

my amp is a yaqin mc100b. the tubes i have installed at the moment are.....
2 x psvane 12ax7t`s
2 x brimar 6sn7gty/cv1988`s
2 x sylvania 6sn7gtb`s
4 x electro harmonix kt88eh`s

many thanks in advance guys.
grayf
Mechans,
I have often wondered the same things, hence, never bought from him. I want ongoing communication and if I fast pay desire fast ship...tubes appear to be good, even if top-tier cost. I've scored some real bargains here on the A'Gon.
The Amperex Bugle Boy 12AT7s arrived yesterday. Does anyone know if there is a significant difference in tubes labeled/marketed France, Holland,....mine are labeled GR BRITAIN ??
I have not had a chance to listen to them yet. Thanks
The Holland tubes are reputed to sound the best. That has been my experiece with 12au7 Bugle Boys.
I guess it is no big deal...but the posting I responded to had the 12at7's listed as made in France. Then they are labeled GR BRITAIN. I really dont know enough about tubes to know the tricks of the trade...Are all bugle boys labeled GB?
I started listening to the Bugle Boys today. Right out of the box the overall presentation is smooth compared to the Golden Dragon. Any ideas on a decent break in period?
Im gonna wait a bit and do A/B comparison.