"Oh my God," he says, shamefaced at slighting the taste of such a group of women. He slams into reverse and hunts for a more diplomatic adjective than 'awful.'
"It certainly is a unique contribution to the art collection in Parliament. I couldn't think of better lighting for it. It has been very carefully thought through."
It is in a dark corridor of Parliament, in an area where no members of the public and few MPs would go.
Mr Finlayson has managed to find a spare 45 minutes between signing Treaty of Waitangi claim settlements - as Treaty Negotiations Minister - to take the Herald on a grand tour of the parliamentary collection.
There are more than 3000 pieces, including the big names: Grahame Sydney landscapes, four Colin McCahons, Len Castle, Ralph Hotere, Philip Trusttum, Brent Wong, Stanley Palmer, Frances Hodgkins, Dick Frizzell, and several by the ubiquitous Unknown Artist.
Mr Finlayson is not one to be seduced by the power of a name, however.
He is an honest, if brutal, critic, designating most pieces to the categories of either "boring" or "bleak".
Old political cartoons lining the passageway to Bowen House get "these are boring and need to be replaced". Large landscapes in select committee rooms are deemed not worthy of looking at: "Not these - they're boring."
Prime Minister John Key's favourite piece is Colin McCahon's Koru. Mr Finlayson is kind about Koru, but possibly only because it is in the Speaker's Lounge and the Speaker, Dr Lockwood Smith, is there when we drop in.
Mr Finlayson manages to muster up something about the admirable "texture" of the piece, which Dr Smith informs him is worth about $300,000.
But the Speaker was not there just five minutes earlier when Mr Finlayson trotted past two other McCahons - A Piece of Muriwai Canvas and Necessary Protection I - glanced up and sighed. "He's a strange one, isn't he? I just find it all a bit ... bleak."
His antidote to the bleak McCahons was in the next room, where one of Gretchen Albrecht's bright abstracts dominated one wall. Then it was back to bleak with a Ralph Hotere ("too dark and gloomy") and Simon Kennedy's Stoat, which features a fetus-like stoat floating above the Earth on a black background.
"There is too much gloomy art in New Zealand. There is not enough light and frivolity."
What he likes in his art is "a bit of colour, flippancy and frivolity. I like humour and a bit of cynicism."
The Herald thought he might be taken by Robert Ellis' Megalopolis II: Motorway Journey, given the National Party's fondness for its Roads of National Significance. That didn't impress him either, although he did enjoy the Frances Hodgkins opposite it.
He also likes Darcy Nicholas' Return to Taranaki - not as much for its artistic merits as because he was about to sign agreements in principle with Taranaki iwi wearing his Treaty minister hat.
That other role also affects his opinion of a sketch of Governor Grey which he turns from with lip curled. There is some discussion about whether Grey was a tad racist.
"He was, actually," Mr Finlayson says. "He's caused a great deal of problems for me, I can tell you."
The Parliamentary Collection is an under-appreciated resource despite attempts to ensure the public can view it. Some of it is used in exhibitions in areas of Bowen House and Parliament House and other pieces are on the walls along the route the public tours take - which about 73,000 people went on last year.
However, most of it is down corridors only MPs and staff can access, apart from occasional organised art tours which only 600 people took part in last year.
It is often taken for granted by Parliament's own occupants.
The art comes from various sources. Some is bought, some gifted or donated.
Unless they have permission from the Prime Minister, ministers must leave gifts of value with Parliament rather than keep them. So there is the "Helen Clark Collection" including pieces by Albert Wendt, Burns Pollock and a korowai (Maori cloak).
One person's art is another's tacky souvenir and the smaller 'John Key Collection' includes a portrait of Mr Key in coffee beans from an Asean meeting, and signed and framed Rugby World Cup jerseys.
Mr Finlayson himself has donated a couple of pieces to the Parliamentary Collection, including a "whimsical" Piera McArthur, Old Holy Men in Zagorsk, which she gifted to him and he passed onto Parliament.
Mr Finlayson's own favourite pieces are in his office and aren't part of the Parliamentary Collection at all. They include another Piera McArthur, of Bishop Pompallier, which is his own.
The minister says he likes the optimism and wit of McArthur, who came to prominence for her art as a diplomat's wife in countries such as Russia and France.
He is impressed to hear that Lockwood Smith has bequeathed some art to the collection after he dies. Mr Finlayson thinks more artworks should be donated.
A few Toss Woollastons might be appreciated - just nothing boring, or bleak, and nothing in apricot.
Parliament art
3000 pieces in collection
$12m total value
73,000 people a year take public tour of Parliament Buildings
