Mine are kinda crusty, but there's no evidence of any leaks anywhere, should i replace them for piece of mind. (better keeping that piece of your mind in your skull rather than on someone else's windscreen)

I'll post pics if ppl want... when i get my bug back...

If they are the original ones, they have an inner tube and the outer tube you can see, and the brake fluid makes the inner tube perish and collapse so they don't work properly anymore. Replace them for peace of mind. You need a special sort or ring spanner that's open on one side to get around the line without twisting it...

I dunno it they are the orig ones. 50 year old brake lines that still work? It is possible to replace the lines yourself without much hassle?

Replace 'um just don't use copper nickel ones (cheap) go to a brake place and get the new oe stuff . Copper was good for sealing but weak and copper nickel is strong but a sh#t to seal
Just my 2 bob

i am in the process of replacing all of mine aswell ,just for looks and peace of mind ,my lines had some small crusty sections so i am just doing the lot.
you will need to get a double flare tool ,there are cheap ones that do work but i think its better to spend alittle more and get a good tool ,i bought a 'rigid' ,it works well . i just cant find a small pipe bender .i have been told to just bend with the hands but i like things to be neat and tidy

I got this one from a Plumbing supply place-it's a Rigid as well and can do down to about 35mm radius.Was about $60 from memory.