Tahoes are generally very reliable.
I love our Tahoe! It has been a great car. We have had it for about 12 years and it has been very reliable and is still going strong. We've kept up on repairs and I am sure that is helped it is lifespan, but really, it has not had to many big problems. We have leather interior and are pretty rough on it so the seats are torn but that could be solved easily with seat covers. The CD player is not reliable and one of the doors is having a problem. I haven't looked into fixing it yet, so not sure if it is a big deal. Ac works great, which is important since we are in az. As far as drivability, our Tahoe has no problems. It handles very nicely. We do lots of road trips and it does great. I have a large family and would probably lean towards a Suburban next time because I don't feel there is adequate room for trips and groceries in the Tahoe. It looks big, but really there's not a lot of room.