Demon Max is very good with treating for wasps and other insects. You will use 1 fl oz per gallon of water. Be sure to spray in the areas that they will come in contact with the insecticide. This can be used every 30 days as needed.
Its hard to say which one is better with out knowing exactly where and what you are treating for. Both are going to offer a good kill and a long lasting residual though initially Demon Max may have a faster kill because it is oil based. On the other hand because Demon Max is oil based it could stain old paint/siding and it does have an odor. Bifen IT is known to be super gentle on most plants (do not use on edible vegetation). Both products can be used indoors and outdoors and both products are safe to use in houses with children and pets.
If you have older siding and are wanting to treat for boxelder bugs and other overwintering pests on the side of the home, as well as mosquitoes and various other insects, we would not suggest going with the Demon Max. The oils in the product are very likely to stain the side of the home. We would suggest going with a product like Talstar P instead since it will dry clear, there will be no risk of staining or discoloring, it is low odor and can be used for overwintering pests as well as mosquitoes and others. Talstar is mixed between 0.5 - 1 oz per gallon of water and can be used monthly or quarterly for pest control. If your neighbors are not treating then yes that will certainly make your applications a bit more of an uphill battle so try to encourage them to treat as well or see if they will allow you to treat the main areas of insect populations as well. You can spray trees and bushes for boxelder and beetle control to help reduce the numbers that make their way to your home.
Demon Max is labeled for roaches, and you may mix this product with an insect growth regulator such as Gentrol for better control. You do not need to mix Demon Max with another insecticide. When applying these products indoors, we recommend also using a professional roach bait gel in areas where you cannot spray. You may want to look over our Roach Control Guide for more information on treating and preventing roaches.