It depends upon which brand you want. I haven't found a price on the stock tubes, but most audiophile types are high on Gold Lion tubes, which would total about $270 for six of them. The type of tube apparently has a significant effect on sound and some are better than others. if I overruled myself and bought one of these, it would mean (based upon an average of 4 hours daily use, which is on the high side) replacing the tubes about every 5 years. With the ARC, the tubes are a bit more, but there are only two and they have shorter life spans, so that's $110 every three years.
My complaint with the 2300 is that there are two tubes which are serving no purpose which would nevertheless have to be replaced. There are two for the linestage, two each for the MM and MC phono inputs. I wouldn't use the MC input.