Eagle 90 long term experience

i could not get shifting on the 3rd gear right. 

i'm on axs transmission now and don't have that problem anymore

I have that problem but I dont think its eagle 90.. hear me out.. I did swap out all electronics out of the box (bike came with full XO) for eagle 90 stuff , kept the XO cassette... 3rd gear would skip  skip.. I had to jump above and below it always.. I though it was the eagle 90.. got another t-type cassete and moved my eagle 90 shifter/derailleur to another bike, put the new t-type cassete (garbaruk) and voila, no issues.. put the xo shifeter/derailleur no my original bike with the xo cassette... same issue 3rd gear.. pair the the garbaruk cassette with the xo transmission shifter/derailleur, works like a charm.. so the cassette is faulty, that ring has a defect..

Running a rental fleet equipped with 90 and using it on my personal bike for more than a year now, it gets pretty high marks from me. First time setup watching the sram video is probably the worst part of the experience but once you remember the steps, which key and setup cog fro your bike etc.. it's incredibly a consistent and efficient install. Robustness Is really where it knocks others out of the park. We have other bikes running a typical derailleur that come back unrepairable all the time. Almost never with the 90, at worst a slightly bent lower cage which is cheap and extremely fast to swap out. Compared to the AXS I would say is a worse on trail shift experience fractionally, but for the price gap and the fact you are almost guaranteed to have to deal with a warranty for AXS at some point, the 90 is a no brainer. The level of replaceable parts if needed on the 90 derailleur compared to the AXS is also pretty phenomenal. Have seen some quality issues with the XS-1270 (HG) cassette with warped teeth causing skipping. The 90 shifter is a bit lacking in terms of quality and I wish they'd get rid of that dumb 'stealth' routing angle of the cable but until there is another drastic innovation in the drivetrain world it's the go to for me. 

nope, i reused the cassette on the new bike. 

I've had mine for a season now. I'd recommend. 

Setup was kind of stupid until I followed the directions EXACTLY. Then it works pretty well. The first few rides I had to spin the barrel adjuster around for a while here and there, it would sometimes get weird with the biggest gear and kind of munchy somewhere around gears 3-5. IDK exactly why but I'm assuming it had something to do with the rear mech kind of wandering around as the new shift cable stretched out over the first few weeks. And I'm suspect that it feels best after you get the barrel set as you're riding around and the bike is at its natural sag point.

 I think its pretty awesome, maybe if you are a shifter-phile it isn't great, but it feels really smooth under load, like surprisingly smooth. (I'm coming off of pre-transmission eagle which I also thought was decent but I'm not picky.)

The only real gripe I have is the shifter. Its fine and works but it is pretty shitty. I heard all about it before buying but I assumed it was overblown. It is not. I don't think its a deal breaker but it is kind of just shitty. If they made a 110 that had 2 gear changes on the down and 3 on the up all of my dreams would come true. I don't think that will ever happen.