There is nothing wrong with the March FX. If it suits your needs better than the TT, by all means, get it. I don't own one, just have shot behind two. I seriously considered one for a while. I had an F 3-24Ć52 for a couple years, but eventually sold it to buy another TT. The FX is a better scope than the F, however.
I just prefer the TT for myself. I have four of them. I have hunted a lot with them. And I shoot a couple of them out to 1500+ at least once a month. The only thing that limits me is on my 6CM, I run out of elevation adjustment at 1400 yards. So I dial, then add holdover for 1500 yards.