Pipe sweating

I consider myself a more than average DIYer. I have been sweating a lot of joints this past week in my new house to replace some faulty valves. Not one joint leaked. This was all on ½ inch copper.

My first question is: How good are my joints? They seem to hold nice and I see a nice silver ring of solder to show a continuous flow. Can I assume this is a more than efficient bond?

I do see a valve that has a rusty stem and does not turn that also needs to be replaced. It is 1 inch copper. Is the larger diameter copper the same effort as the smaller ½ inch? It does look a little bit more intimidating.

And finally,
How do I know if I need to remove the rubber fittings in a valve when sweating? Do all valves have these or just certain ones?

When I was taught to sweat we cut our joints lengthwise and then tore the halves apart to examine the solder coverage. Solder on the outside does not necessarily mean solder on the inside. Take some time with soldering half a joint at a time and you can see if the solder penetrates all the way to the end of the tube.

The 1" will take longer than the 1/2". If you're using propane with a non-swirl tip then it'll be a pain heating the valve. MAPP gas and swirl tip and it's almost as easy as 1/2". Pay attention to local temperature in the joint.

For your last question, don't buy valves with rubber parts. Go with ball valves and teflon seals then heat is not a problem unless you just go nuts with the torch.