First, let me say I am NOT an expert on this subject, so these are just my opinions formed from reading. Yes, there appear to be two levels of steam cleaners - the $100 and under range and the $300-500-$2,000 and up range.

Many people on this forum are very happy with their Shark Steam Mops. It would seem that there is either something wrong with your machine or your technique in using the Shark. My guess would be the machine. These are inexpensive products mass produced in China, and some percentage of them are defective. Send it back and get a replacement.

I have one of the higher end steam cleaners. The difference seems to come down to the temperature of the water, the size of the water tank, and the amount of steam vapor the machine puts out. For example, the Shark company doesn't give any information on the water temperature, while mine heats to 302 degrees in the tank. The cost of the higher end steamers seems to be in the heating element and the type of tank.

I had not heard of the TANC system on the LadyBug, but found a page on the web that describes it:

Our Ladybug includes a Thermal Accelerated Nano Crystal Sanitization (TANCS), a device that turns the minerals in tap water into nano-crystals. These crystals, when heated from 210°F to 220°F, are energized to provide micro-abrasion to break through dirt and bio-film layers on surfaces. The system acts as a poultice; as the heat expands and then dissipates, it pulls out dirt, oils, etc from surfaces onto our cotton towels. Within seconds, this system can deliver a deeper, cleaner, and sanitized surface. It makes surfaces look new again!

Again, I'm not an expert, but that sounds like a description of steam cleaning, and every other steamer out there does the same thing - boil tap water and spray it out! So if LadyBug has a TANC system, then they all have TANC systems.

The Allergy Buyer's Club site has lots of good info, but keep in mind that it is still a sales site. They seem to only review products that they sell. Don't confuse it with the independent reporting of something like Consumer Reports.

Here is a link that might be useful: TANC system on the LadyBug