I've recently replaced a Schwalbe Big Apple (406-50) with a Kenda Karrumba. It seems to be well-known that the Big Apples have low rolling resistance at appropriate pressures for a 50 mil tire. Is this also true of the Karrumba? The Karrumba can go up to 100psi(which is quite a bit for a 50 mil tire I think), but I'd like to run it at more comfortable pressures.

My issue is that the Kenda tire seems to me hard and tough (relative to the Schwalbe) and I've read that works against a tire having low rolling resistence. Kenda says "...the rounded profile paired with Kenda's DTC rubber that has STICK-E rubber on the sides and L3R Pro compound on the center tread gives you speed and cornering grip at any angle." My understanding is that L3R Pro is the low-rolling resistance stuff Kenda uses. Is it comparable to what Schwalbe does?

The Karrumba is essentially half the price of the Big Apple, and am wondering if keeping it on the bike is worth the savings.