Maybe comparing Rajah and Truncata is like comparing Reticulated python vs. Anaconda? One is the longest and the other is the thickest/biggest.
Of course very difficult to do, but hopefully we can get some data in future which species does produce the biggest pitchers in terms of capacity (liters, etc) this is probably the best measure.
All I know though is the Truncatas are infamous or famous to have pitchers big enough to catch and kill rats! Then again I imagine Rajah would be able to do it too.
TTFN
Arvin
ps. After posting I saw Jeff's post, I should have just agreed with him when he said largest depends on how you look at it. However Jeff for me I'd not count Peristome in the tally
But as you said it's a personal score card.