10x mag is a favourite so you might just want to put your money into a good quality fixed mag scope, and not compromise any quality for the sake of getting a zoom facility.
If you are planning on using the divisions of the ret to assist with rangefinding then a ret with half mildots not just full mildots might be preferable.
Subaru, my club's present HFT course starts off with a 54 yarder and the target is a rat facing downhill at about 30 degrees. It is a pig to rangefind by conventional means; it's the first target so the shooter has had no trial easy shots to find the wind, and it's seldom a 2 on the card. Devious? Probably. But isn't that part of HFT? The last target is a 13mm reducer at about 13 yards, and the lane is at a different angle to the wind compared to all the previous lanes. That's not often a 2 on the card either. In between of course we have a load of gimmes................. (not!)