As I understand it, the Trijicon, Delta and Athlon and Tract all come from the same plant, Tract uses German Glass. Apparently the Apex comes from a different Jap plant, Zeiss V4 is apparently a Japanese scope with Zeiss glass in it.
I have the Delta stryker Gen2 4.5-30x56, can't ##### about it at all, bought it sight unseen, no regrets. The Gen3 they are selling now, apparently has upgraded parallax, remarked turrets. The 10yr warranty is no big deal, they are usually either good or bad right off the bat, and by the time 10 yrs rolls around, you usually either had your money's worth, or got rid of it. There are higher end scopes in other Euro brands that are 10yr warranties as well.
Also have a Tract 4-20x50 30mm PRS, also bought sight unseen, took a while to get, had to do some paperwork which they made really easy, but, was worth the wait, very well built scope with really good glass and a nice reticle. I wouldn't be reluctant to buy a 4.5-30 off them either, it'll just take a while to get one.