House Plant Compost

Is it worth buying house plant compost? 
I have a few that need potting on this year, Swiss cheese, dragon tree, mother in laws tongue and the like, so not specialists like orchids. I normally just use a mpc and most of them are at least 15 years old now, but wondered if there was some special ingredient I wasn't aware of. They don't get fed, either!

I just use normal MPC, but I do feed mine once or twice a year with normal tomato feed. That might not be right, but they seem happy!

I need to repot some plants too and when I get round to it I'll use whatever I've got to hand, which will probably be MPC. Because my plant are in dire need of repotting (and have been for years) I tend to dose them with baby bio to assuage my conscience.

Thanks all!
Basic mpc it is then, and I might give them a feed too.
The houseplants all go outside for the summer and live on the covered terrace so they're not in full sun. I guess they can have a dose of comfrey tea when all the rest of the pots get some. As long as it's a long time before they come back indoors!

I think that anything in a large pot would benefit from a John Innes type compost. These are loam based and heavier so pots don't fall over or get blown about. Long term potted perennial plants benefit from JI no 3 compost methinks.