Yes, in most cases, more vacuum is better.

Some prosthetists have reported that too much vacuum in an elevated vacuum socket causes discomfort and "pulling" and too little fails to provide linkage between the socket and the residual limb. The argument goes that there is a "sweet spot" at around 10"Hg. One set of pump instructions even recommends "only enough to suspend the socket".  This is not a good reference since actually the the socket can be suspended with no vaccum at all using just the sealing sleeve. The goal is to achieve the best possible linkage, which is achieved with maximum possible vacuum.

Experience suggests that, just as in traditional suction sockets, discomfort and pulling occurs when there is lack of total contact or a lack of even socket pressures. If the fit of the socket is correct, the vacuum can be much higher and the linkage much better. I suggest that, if there is pulling and discomfort, check the socket fit distally BEFORE simply having the patient use less vacuum. The exceptions would be with invaginated and severe scarring and adhesions where vacuum may intially have to be reduced.

Evolution Liners recently introduced the Aura Sealing Sheath. When used with elevated vacuum, it allows the prosthetist to use a custom silicon or polyurethane liner and then apply a sealing ring between the liner and the socket just below the socket brim (the prosthetist determines the height of the sealing ring).  This system trumps the complexity of the double wall system and maintains the a more secure proximal skin contact than the single wall systems in which the liner is reflected over the outside of the socket.

For transfemoral applications, there are now three socket design options listed here with thier advantages:

1. Double wall socket- Provides ultimate vacuum and suspension in any range of motion.  Because the liner and sleeve make up most of the inner socket, it is flexible and conforms to variations in residual limb volume more than any of the other designs.

2. Single Wall System With Aura Sealing Sleeve- Provides many of the advantages of the double wall system but much simpler and lighter.

3. Single Wall System With Liner Reflected Over Proximal Brim of Socket-  The simplest elevated vacuum system, though less flexible and accomodating than the others. 

The Aura Sealing Sleeve is a valuable addition to the prosthetist's choices of socket componenets.