While I have not done RSV out of ORD, I have been on RSV in SAT, IAH, and CLE for almost 4 years. My experience:

Days Off: As was stated above, either 11 or 12 depending on the bid period but you could get 13-14 if you hold a Floating Reserve Line(FRL). My opinion on the FRL's is that they cant be that bad if I am at the bottom of the list and never get them.

Reserve QOL: All comes down to this, Commute or Live in Base. Commute to short call Reserve and your QOL will be non-existant.Commute to a Long-Call(12 hour call-out) line and commuting is doable.With short call Expect between 5-7 days at home a month after you commute in a day early and home a day late. I did this for 2 years in CLE and it sucked big time. However, if you live close enough to base that you can sit Reserve at home it really isnt all that bad. I have come to find that not getting used 1-2 days a month makes all the difference. After the 2 years of Hell in CLE I really feel like my batteries are re-charged now.

Expect to be busy from March-August and then things chill out a little bit during the fall and winter. ARC(Ready Reserve at the airport) is in 4 hour blocks for 4 hours of pay. Good time to do all your revisions.

My biggest complaint of our RSV lines is that they come in mostly 5 day blocks. Why we cant do 4 days blocks I dont know.

I think you are getting in at a good time and will not be facing endless Reserve. Things are looking up now that we are under new, seemingly competent management. Good luck with training and the first 2 rounds are on me when we fly together. Expect tequila shots.