Below is a shortlist of some producers I would recommend looking out for, followed by a selection of what I consider to be the highlights of each portfolio of labels:

Bodega Benegas (Mendoza)
- best known for its Bordeaux Blends & super-old vine Cabernet Franc
- makes an excellent Sangiovese & Syrah
- best wines made under the Benegas Lynch Brand (Meritage)
- also has a couple of excellent QPR everyday wines (Don Tiburcio, Juan Benegas)

Escorihuela Gascon (Mendoza)
- Syrah-Cabernet blend, excellent high-end Barbera
- very good QPR whites (Viognier, Sauvignon Blanc and dry Tocai)
- top of the line labels made under Miguel Escorihuela Gascon labels

Bodega Sur de los Andes (Mendoza)
- Infinito Malbec (icon wine of this producer)
- Malbec Grand Reserva

Achaval Ferrer (Mendoza)
- Malbec Mendoza
- Quimera (blend of cabernet malbec merlot & cab franc)
- Dolce (Passito style dessert wine)

Familia Zuccardi (Mendoza)
- Zeta Tempranillo-Malbec (icon wine of this producer)
- Malamado Fortified Malbec (Port style)

San Pedro de Yacochuya (Salta)
- San Pedro Torrontes (white wine)
- Yacochuya Rolland (very powerful high altitude malbec)

Bodegas Catena Zapata (Mendoza)
- Catena Zapata Estiba Reservada (cabernet based blend)
- Angelica Zapata Malbec Alta
- Angelica Zapata Chardonnay Alta
- DV Catena Cabernet-Cabernet

Rutini Wines – Bodega La Rural (Mendoza)
- Antologia Series (various varietals & blends)
- Felipe Rutini (Bordeaux blend)
- Vin Doux Naturelle (Sauternes style dessert wine)
- QPR Coleccion Cabernet-Malbec

Trapiche (Mendoza)
- Medalla Blend (cabernet malbec merlot blend)
- Iscay (merlot malbec blend)

Finca Las Moras (San Juan)
- Mora Negra (bonarda malbec blend)

Callia (San Juan)
- Gran Callia - Reserva del Enologo (blend)