Good choices, just make sure to feed the appropriate amount to get the full nutritional benefits.
Feed is by weight. Triple Crown lite is 1-2# per 500# bodyweight, so a 250# mini would get 1/2-1# daily (other sizes will need a bit of math to determine appropriate amount to feed). I'm pretty sure TC Lite is about 3 cups per pound (standard dry measure kitchen cup, weigh to verify). Triple Crown senior as a minimum of 5# per 1000# bodyweight, so a 250# mini would get 1.25# daily (TC senior is 1.08# per quart, so about 1/4# per cup). TC provides a marked scoop for their feed products, if your feed store doesn't have them, contact TC and they'll send one to you (not sure if it'll have small measurements that will cover a mini's needs).
I'm currently feeding TC senior to several of mine; as a carrier for supplements for most, but a couple needing to gain are getting up to 1.5# daily; all but one love it (he's on a different feed)
Yep. We are giving the girls 1/2lb of lite and the gelding is getting 1.5lbs. He does eat hay, but he doesn't get the full value of it. After a couple weeks we are going to re-evaluate whether to increase the amount or keep it the same for him. I tried to get a scoop, but they didn't have one at our feed store. We have a kitchen scale to measure it out, so that works for now. I'm excited to see how they change over the next while. Both girls are overweight and the gelding needs another 20lbs or so. I need to get pictures for before/after comparisons. My kids and I hoping to show this summer 
