In other posts I've written about how little my own listening impressions of speakers square with reviews in magazines. That holds true, to a large extent, with individuals here too. If you spend enough time here, you'll start to recognize just a few names that, most of the time, seem to be hearing and describing something similar to what you are.
Case in point: Thiel. Check out a few threads and see the variety of adjectives used to describe the sound.
Another case in point: Harbeth Super HL5 Plus. I got to listen to these recently. Pretty much everything I'd read on here led me to expect a certain kind of sound, and boy was I surprised when I heard something quite different (a lot less relaxed and warm, BTW, than anticipated).
Moral of the story: unless you audition both in person, you'll never know. You might as well toss a coin, buy one, see if you like it, and if not, sell it here and move on to the other. (I'm assuming that auditioning them in person is logistically impossible.)
Received wisdom says that Spendor will be a bit more restrained and forgiving, but remember that this is a new and quite different design. It also says that Totem will be a bit more revealing and fast, but who knows what the "Signature" modifications to the Forest do to its sound. (I heard a Sttaf and again was surprised that it didn't sound bright to me.)
It's great that you've given us all the details of your room, your system and your musical tastes, but the one great imponderable that can never be quantified is your personal set of ears.
