I was also in the market for new boots recently. Here is what I found. SG10's are too narrow for my D width feet. Oxtar's bulky and the straps were a definite point of failure (plastic--not the strap itself, but the buckle).
Tech 10's well let's see. I am and will continue to wear my old T8's, it's just a damn good boot, comfy for all day wearing, walking the pits, riding, protection. So I thought the T10 would just be a big improvment. I was wrong. See for yourself, I think Alpinestars missed the mark on the T10's.
My final choice after lots of shopping and consideration was the SIDI SRS. It's a low profile boot, lots of protection, very thick sole, and they were as comfortable as my T8's, but much lighter.