Hi Ajay,
In that no one else has attempted a reply regarding speaker stands for the XLs I will give it a shot. I will assume no background knowledge and apologize if I am too basic for you. A stand that is a good match for the XL Sapphires will serve several functions.
First, it must support them at the correct height, which is generally the height at which the tweeter will be at the same level as your ear at your normal listening postion. This of course varies depending on where you sit and how tall you are, but 25-26" seems right for most folks with the XLs. The tweeter sits 9.5" above the base so you can measure the distance yourself. Getting this right is the most important, it effects not only stereo imaging but tonal balence as well.
Second, the speakers must be stable and not fall off or tip over under normal family traffic. Did I say point 1 was the most important? This is the most important. The XLs are 13" deep, 7.5" wide at the front (where a lot of the weight is) and 8/5" at the back and they are heavy for their size. The top plate should match this pretty well and because the speakers are heavy the stand should be too so it doesn't get tippy. The interface between the speaker and the stand here is real important so the speaker stays put.
Third, the stands should absorb resonances from the speaker cabinet and either absorb them or transmit them to the floor. This is particularly important with relatively small speakers that have very powerful drivers, like the XLs. A very heavy non-resonant stand that is well coupled to the speaker, then coupled to the floor with spikes, will result in deeper cleaner bass with more punch, more solid imaging, and even greater detail. The weight of the stand as well as the materials it is made of are important. The Sound Anchor stands are heavy steel and filled to damp resonance. Equally important is how well the speaker cabinets couple to the top of the stand. You do not want to isolate the vibrations from the stand, like rubber feet will probably do. Instead, you want to transmit the vibrations to the stand. Spikes do this, as does bolting the stand to the speaker. The XLs do not have screw holes for these options. Most folks on this board seem to think that small sorbothane disks or Blu-tack are the best way to do this with the XLs. (BYW, check out this link for a review of some stands that take these concepts to the extreme).
http://www.innerear.on.ca/reviews/accessoriesimagemaster.htmlAs to your specific question. You do not say how tall the Sanus stands are but check that first. The Energy Veritas stands in black would look great with the XLs, but I see nothing that says how tall they are and the Energy Veritas 2.2 are much taller than the XLs, so stand height will probably be a real problem with those.
I do not know how heavy your MDF stands are, but using Blu-tack in place of the rubber bumpers would take better advantage of any anti-resonance properties they have. You say they have rubber spikes to the floor. I have not seen those but metal spikes may better couple the stand to the floor to better take advantage of its infinite mass.
Will the difference in sound be worth the cost to go for the Sound Anchors? For a small speaker with the qualities of the XLs I think it would be well worth it. While not as pretty as the Veritas stands, they are handsome enough and do everything right in terms of resonance contol and stability. In my experience high quality stands make a bigger difference than esoteric speaker wire or interlink cables. I will get mine on order to beat any possible price or shipping increase and report back when they arrive.
Hope this helps - George
