Have you done a fair bit of boiler work before? If so then you will have no problems. If not then i would consider the threaded stays as the easier option.
If your boiler is completely finished ie backhead and foundation ring etc already fitted, silver soldering the stays may not be a simple task for someone with limited experience.
The stays would normally be silver soldered before the backhead and foundation ring are fitted.
There is no reason why anyone should fail a threaded boiler stay. Many people are still using them especially in the smaller gauges.
Edited By jason moore 1 on 07/09/2013 08:55:06