Well, after reading this thread I gritted my teeth and stumped up the £34 (including £9.50 for delivery

) for 2 litres of Redline MTL.
A couple of months ago, I had changed the gearbox oil for some 80W/90 I got from GSF. Was shocked to find my gearchanges were worse! 2nd gear crunch was no better and was very notchy when cold and it had even developed a crunch going from 4th to 3rd. Even my Mum noticed!
Anyway, the Redline is far better. 3rd gear crunch has now disappeared again and shifts are alot smoother now. Not sure its got rid of the 2nd gear crunch but its definitely easier to engage from cold.
Interestingly, the hot 80W/90 I drained out was thicker than the cold Redline MTL. I'll be keeping a close eye on it after somebody on here commented that Redline MTL leaked out round his driveshaft seals.