This is a very good, well made kit - and an exceptional value. I used it with two 30" wide doors glued together with biscuits. All four hanging rollers were used, two per door. It works well, and was pretty straightforward. Cheers!
We installed this with a pair of antique solid wood doors and were not concerned by the weight because these are very sturdy. Super easy to install. Already sent this link to 3 friends because it was such a great deal for the quality!