first bottle - last bottle
1. Cathy Gale

first bottle shared: Death Dispatch
last bottle shared: The Outside-In-Man

2. Emma Peel:

first bottle shared: The Murder Market
last bottle shared: Murdersville

3. Tara King

first bottle: The Curious Case of the Countless Clues (first bottle at her flat)
first bottle shared: Get-A-Way!
last bottle shared: Bizarre
Champagne - the most bottles...
The most bottles of Champagne can be seen in series 6 episode Who Was That Man I Saw You With?

The most empty bottles appear in series 5 episode Who's Who???, when Basil and Lola drank four of Steed best Champagne bottles.

The most filled glasses were used by Steed to build the Champagne fountain in series 6 Who Was That Man I Saw You With?

The largest Champagne bottle was brought to Steed's flat by Tara in Legacy of Death.

The most destroyed Champagne (empty) glasses appear in Legacy of Death.

The worst Champagne that Steed ever had to drink was served in Lobster Quadrille.
John Steed's reaction on Champagne of a low epsiode Esprit de Corps
What's Steed drinking?HomeDreams, Fears, Nightmares and Memories

Steed's favourite Champagne Meudon & Heim is not a real brand, that Champagne does not exist.
Steed's Biography
The Alcohol Statistics