Too many problems with that offer.
1. The software stops working after one year.
2. The free, lesser version available on Auslogics site raises too many red flags at Virus Total ; some of them possibly benign, being marked as PUPs, but not all. And even PUPs can be very annoying.
3. It seems the software breaks restore points (or may break them). What good is a potential, alleged speed gain (with no precise figures being given anyway), if you lose a safety feature which might save your bacon some day ?
4. The licence basically claims that the publisher can brick the software when it likes unless you pay :
“Where an update or new release is provided by Auslogics:
(a) you must immediately install the update or new release and Auslogics is not liable for, and will (notwithstanding any other provision of this Licence) not accept any liability for any previous version or release; and
(b) you may be required to enter into a new licence for the new update or release and this Licence (and any previous licence for the Software) will be terminated immediately upon your acceptance of those terms. In the event that no new licence is supplied, this Licence will continue to apply in all respects to the update or new release which shall be deemed to be the Software for the purpose of this Licence.”
That’s not even acceptable for a paid piece of software, and this legalese obviously covers the paid version as well. There are many reasons why someone might chose not to do an upgrade, the least of which being that it might actually be a downgrade, introducing bad features or even breaking things. The paid-for version is actually rather expensive.
Finally, there are knowledgeable people who argue that you should not attempt to defragment further than what Windows does, and that it might actually be detrimental. They also provide explanations (which I’m not able to reproduce here). So in spite of the fact that Auslogics seems to offer more than Windows 7 included defragmenter, and has a reputable name, I’d rather pass.