So let's say I want to keep some transistors on hand

[WISCOJIM]

Originally Posted by TinCanAlley

So, basically, if it's only noted by value I should replace it with a 5% 1/2 watt? I don't think I'd be able to tell the wattage, so the 1/2 watt 5% would cover just about all of them.

Yes, 1/2 watt unless otherwise noted. The originals were 10% & 20% tolerance, but 5% tolerance resistors are now available without the large cost premium they had in years past.