I don't think a GUF2 with a 241 is great value either, as you are only saving 50% of the avios difference compared to a non-241 booking. You have only saved 25,000 avios each in your case, valuing the GUF2 at 50k avios.
An upgraded revenue fare doesn't need award availability.
Indeed I think it is a bit if a waste using a GUF2 n combination with a 2-4-1 redemption, you only save 50k Avios. If you use it without the 2-4-1 you can save more than 100k Avios depending on route.