I have been cooking beef steak and salmon with sous-vide for about 2 years. The meat quality is excellent. I don't have the equipment but using my home-made device instead;
Creating vacuum - using water displacement method
Cooking - in water pan heated on magnetic oven and monitored with a thermometer for baking
Since the cooking time is about 13~18 min I just switch on/off the oven to maintain the temp. It works for me here.
Now coming to sous-vide lamb chop/rib I made a searching on Internet and found the cooking time is ONE hour. Then I need to purchase a sous-vide equipment. Otherwise I have to standing for ONE hour in front of the magnetic oven watching the thermometer.
Could you please shed me some light whether my searching result is incorrect? Thanks