I have a 1990 JTM45 RI that I am thinking of putting EL-34's in place of the 5881's currently in the amp. My question is, is there much of a difference between the 2 amps tone wise other than wattage and headroom? I have listened to many 1959 amps (original and RI's) but I have never sat down and played a 1987 to compare with the JTM. My understanding is my amp has the good Drake transformers (saw them when I removed the chassis) and is more than capable of running the EL-34's with no mods. Is that correct?