Does anyone have any experience with termite baiting system (such as Sentricon, FirstLine, etc.)?

We have a 80+ years old wood framed house in N. California that has a few termite sightings from our basement level that we can see. We just had an estimate from a large termite co. who proposed termiticide foam barrier system (termidor?) which require drilling down through our newly poured concrete foundation and slab, and some foam treatment inject into the wall voids. The price seem rather high $2000 plus a $300/year optional maintainence for 7 years! Does this seem reasonable?

We are not too sure of the idea of drilling through our concrete foundation and slab even though structurally it's probably ok. Just want to know if other options are available? or reliable? We have been doing a lot of research on-line but not too much real facts. Please help!

Thanks.