Anyone care to make a recommendation for a top end place featuring good wine and food?

Aramburu for sure! Can't go wrong with Don Julio if you are looking for steak.

You need to tell us what kind of food and ambiance you would like, Marko.

Lunch or dinner?

I assume you are talking about BA.

Have a great time in our country.

Dinner please, staying in Recolleta.
Something typical and experiential of BA thanks AV, wine orientated please.

In the Recoleta:

For steak or grilled fish, research:
http://tinyurl.com/6y4sdhq

For Italian, research:
http://tinyurl.com/8pyo2l4

I don't drink, but I guess good wines should be available in both, at a price, of course.

Both places are rather high end and cater predominantly to locals, particularly at this time of the year, which is low season for tourism.

One step higher, you can research: http://tinyurl.com/omd9meo I find it a little overpriced, but, after all, you asked for a "top end place featuring good wine and food", so, there you are.

Have a great time in our town.

I went to Tancat for dinner and it was the best meal we had! Great seafood. We didn't have wine but I would expect the wine to be great too. Would recommend you reserve in advance as it's very popular among locals as well.

Never been to Tancat and it's obviously a matter of taste, but the reviews it gets on a local restaurant rating page are just OK: http://www.guiaoleo.com.ar/restaurantes/Tancat-231

Besides, I don't think it "fits" the OP's specifications.

Have a great time in our town.

My favorite, high end restaurants in BsAs are:

EL MIRASOL in Recoleta: http://www.elmirasol.com.ar/
El Mirasol de la Recova is a block from the Four Seasons. They serve some of the best steaks in Buenos Aires (and other wonderful dishes). It's tucked away under the overpass on Posadas: Posadas 1032.

& TOMA 1 (Centro) http://www.guiaoleo.com.ar/restaurantes/Tomo-I-81Carlos Pellegrini 521, - Eclectic, creative upscale - really fine dining.

I agree with Marnie about Mirasol.

About Tomo I, I have never been, even though I have been invited several times by forum friends, because I feel it is overpriced.

It is no longer run by the people who started it and made it famous. At that time, the Cóncaro sisters actually cooked and ran the place. Now, the sisters have retired and the place is "just a ghost of its magnificent past", in the words of an unhappy TA reviewer.

really appreciate your input !

We all hope you'll tell us about where you went and whether you liked it or not.

That is what these forums are about.

Have a great time in our country.

I always try to do trip reports.
Information shared is always useful.

A quick question for the locals. I have booked a dinner and tango show at Carlos Gardel. Should I wear a tie and jacket ? Cocktail attire for the ladies ?

There is a wonderful bistro , Las Pizarros Bistro on Thames and Charcas in Palermo Soho. It is a small place, run by a local chef with a menu that changes daily. Entrees are written on a chalkboard, and are incredibly creative and delicious. Reservations needed. It is frequented by locals and some tourists who find out about this secret place! We ate there 2 nights in a row and were sorry to leave BA because of it.
Don Julio is so-so; you can do better. It is overpriced - the meats are ok but the sides are not very good.

Dress standards ? Don't want to create a faux pas with the couture !

Thank you Ichin for the tip of Las Pizarras, my favorite is Restò in calle Montevideo and Calle zparaguay.
Buena suerte.