Okay, so the R stands for reverse terminal layout and is a standardized part code for "group 34" batteries, as well as all the other "group" battery specs. If you look at my battery, the positive terminal is on the left at the top of the battery, it is a group 34R. This is a group 34 NOT R battery:
As you can see, positive is on the wrong side! In case you wanted to know what the other letters mean in the Odyssey-side of the part number, here ya go:
S – stud post
T – SAE post
L – left positive
DT – dual terminal
MJ – metal jacket
MJS – metal jacket with stud post
MJT – metal jacket with SAE post
LMJ – left positive metal jacket
LMJT – left positive metal jacket with SAE post
This battery fit nicely in my vehicle, I used a ¼" pvc spacer (from one of my sign board scraps) at the top just to make sure it was super tight when bolted down If you look at Odyssey's website, it clearly states you may need a height adapter, I decided to just make a spacer for the bracket and let the battery sit flush on its tray.
I did not have to change the cables at all, (I think I bent one of them also like someone else previously stated in this thread), and they are not extended either.
Say what you want, but I'm very happy knowing that I have a great battery in my vehicle, one that will never build up acid whatsoever, and I don't have to spray a bunch of red crap all over the terminals or use those worthless felt washers that always fail after a couple years.
This battery isn't for everyone, its expensive and way more than most folks here will ever need, but when I go camping in summer and I have my ARB fridge plugged in, phone and game chargers running, an air compressor for tubes and air mattresses being run daily, as well as lighting and maybe even the radio, I'm happy to know that I have a battery that can take the abuse of being drained well below what a wet cell battery should be drained below (typically around 35% of its capacity).