Is there really a significant difference? the cost is so much higher and I'm not quite there on the financial side to afford the higher tier. Wondering if its really worth it when its 4x-8x the price of the eth cv

GT/Thresher have better/faster attack speed and also lower str req.

IAS Breakpoints for GT/Thresher: 0 8 22 42 75 142 -> The 75 bp is easily achieveable through something like treachery armor and andy visage + ias jewel

IAS Breakpoints for CV : 0 5 11 22 35 56 89 147 -> the 147 breakpoint is the same speed as the 75 of Thresher/GT, but since even the 89 BP is hard to reach you will most likely be 2 attack speed breakpoints below a GT/Thresher.

Usually you want to look at your merc gear and see which BP fits the best.

For an Infinity i would definitely recommend a GT/Thresher since it's the best base in the most popular gear setups and you dont want to cheap out on the base if you spend 2 Bers. Also Infinityh as Crushing Blow which scales really well with attack speed.

Insight on the other hand doesn't have CB and is very cheap, so a CV is completly fine. (if you can reach the str req!)

TLDR: GT/Thresher are better, but it doesn't matter so much for an Insight, I would also recommend you to go for a CV if you are not rich, which is the best bang for your buck.

thanks so much! very informative and explains a lot about why and what to get. I'll stick with cv as the mana regen is very worth for me right now.