I have the 3.5 x 35mm TA11 with the donut reticle. The top of the donut is 100yds, center is 200 yds, bottom is 300 yds, then there are unlabelled hashmarks at 400 & 500 yds. The 600 yd hash is labelled with a 6.
I frequently shoot at a steel plate that lasers out to between 375 and 390 yds, depending upon which shooting station I'm standing at. The 400 yd hashmark lays rounds right onto the plate.
At 100 yds the donut reticle fits nicely around the black bullseye on the targets I normally use. The bullets land a tiny bit high because the center of the donut is sighted at 200 yds. However, at 100 yds the Bushmaster/ACOG combo will shoot 1.5 inch groups (five shots) with inexpensive PMC plinking ammo. My shooting partner's girlfriend fired one well under an inch. I like the donut for training new shooters---very easy to learn.
I have also used the donut for field use. One elk season I fabricated my own mount and put the TA11 on a Browning Stainless Stalker in 338. The eye relief is a bit short for a lightweight 338, so I had to mount it a little farther forward than I normally would. However, when an elk took off through cover, he was really easy to follow.
I've looked at the triangle reticle at gun shows and feel that it would also work just fine. However, I'm extremely happy with the donut.