I suppose there are better .22 semi-auto rifles than the Ruger 10/22 but not for the money, IMHO.
I personally think there are better .22 autos than the Ruger 10/22, especially for the money.
On the other hand I think the Ruger would make a good self defense gun in the home. It would be OK with just the standard 10 round mag but put a good quality 30 round one in it and it would be especially good.