Hello and welcome to Just Answer. There are no real pros/ cons for SIPs panels. It is just a standard material that is used for post and beam construction. The framing is exposed and often spaced far apart so the SIPs panel is the perfect way to put a "skin" around this type of construction. The panels have good insulation values, the plywood is attached to the outside for nailing siding or roofing to. The inside face of the panel can come finished with tongue and groove wood or drywall. If you need further help or clarification on this answer, please do not hesitate to reply to this post.
There is not much difference in cost, stick framing and post and beam are two totally different methods of constructing, but they basically still use all of the same materials, except for the framing of course. It is basically a matter of taste of what kind of house you want. Post and beam can be very elegant with the exposed timber framing, but running plumbing, electrical, and heating/ cooling can be a little more tricky. You can't simply run the utilities anywhere in the framing such as with stick framing, so careful coordination needs to figured into the project.
Stick framing does not need SIPs. SIPs are used on post and beam or timber construction.....so you are confusing me a little. Timber framed houses will cost a little more but are appraised at a higher value. Time frame will be longer on timber frame due to custom design of framing components and coordination of utilities running through the SIPs panels. I have seen plenty of homes constructed from SIP's, and again they are always post and beam or timber framed. They come out great.
Oh sorry....I just noticed you asked about Insulspan. These are a type of SIPs panel that are used in combination with stick framing. There are still some coordination issues with running utilities in the panels, but nothing to complex. Since the floor is stick framed, much of the utilities are placed there. The panels are a little faster to install and can be pre-made at the factory, so construction time can be reduced. They have great insulation/ acoustical properties and are strong as well. I think they have a good product and their site is pretty accurate, as far as the benefits.
Advantages of SIP's vs. stick framing are:
Initial cost of SIPs will be more expensive than the materials used for stick framing, but the costs can be recovered later with less construction waste, increased site productivity, reduced labor costs, and heating/ cooling savings. In the end, the overall cost is virtually the same with SIP's and stick framing.
Dis-advantages of SIP's vs. stick framing are: