Options on a 2203 6550 build

[k9taxi]

I am looking at buying the master volume 2203 kit with 6550 tubes. If I select the 6550 tube option (+80.00) do I also need to select the transformer option for the "MM-100M 6550's" ?

Can someone elaborate on what difference it will make to upgrade to a MM transformer? I'll check out the Mercury Magnetics web page.

Finally, will the stock transformer provide enough power to add an additional gain stage mod?

Thanks,
Andy

[demonufo]

The MM trannies aren't exactly an upgrade, just a different flavour IMO. Usually more modern sounding, and totally unnecessary when using 6550's.
Stock PT should be just fine. The only noticeable extra draw on the PT would be the heater filaments of the extra tube, which at an extra 300mA shouldn't stress it any.