I have both... and in your price range you will not get the accuracy you want shooting a conversion kit through a 5.56 barrel... the best I could get before buying a dedicated .22lr barrel was about 3 1/2" at 50yds...(CMMG kit in a 16" Colt)

for $150... get a good trigger for your 10/22 (easiest with an aftermarket hammer already prepped, like a Volquartsen), have the bolt worked on by someone familiar with them... make sure the firing pin has no vertical travel, and reduce the headspace to about .045"...if at all possible, attach the scope mount to the barrel... if that is not possible, attach a good Weaver or Picatinny rail that won't come loose...if you have a carbine 10/22 remove the barrel band.. there is a lot of accuracy potential in finding the barrel harmonic node with a home made barrel tuner

good luck...with a dedicated .22lr upper, my CMMG shoots as accurately as my STC prepped 10/22 at 50m

ARFCOM rule....get both

Yes, a few.

Price for what you get.
Fit
Ease of taking rifle apart.
Price...
Who needs a plastic bayonet anyway?
I don't care for quad-rails.
With the ATI you can use the factory iron sights if you want.
The ATI allows you to use, not use or customize your rails.

Its all a personal thing. I just wanted a stock for my 10/22 that fit right and was comfortable to hold and shoot. I personally had no desire to try to make a 10/22 look like an AR. I have over a dozen AR's in all calibers, including a few in .22. Why would I try to make my little 10/22 be a fake AR when it isn't an AR. Its a Ruger and I am fine with that, I just want it to fit me.

YMMV