Bought two Twin XLs and although there were a few hiccups on delivery (FedEx changed the delivery date 3 times; messed up our timing in removing the old King mattress and box springs). Also, one of the two boxes was damaged enough to make a slit of 3-4" long on the fabric that wraps around the frame/structure of the base. Also, the motor for the back (not the pillow tilt) got affected as it works slow and makes a noise when operated. But that was due to damage during shipping as the other base is fantastic! - it works very smoothly at below average noise, the massage is absolutely wonderful, the response is outstanding (with the 1/8 min ON/OFF ratio, or 12.5% efficiency; ...most bases have a lower % which limits operating the motors in a more continuous fashion). The base seems very well built, and looking underneath you can see well designed parts and positioned perfectly. Is there any room for improvement? Of course, always, no matter what product it is, there are things that one can better. For example, 1) The leg rise range is quite small - they could have allowed a higher rise without, btw, adversely affecting anything
2) The pillow tilt too should be given a wider range (again, no additional cost or adversity by doing so)
3) Bottom, foot-side of mattress, when raised at max foot lift, creates a large gap (between the top surface of base structure and the bottom side of the mattress) - that creates a palpitating effect or springiness which is also exacerbated for short people (less weight is applied at the end of the mattress since feet do not reach all the way down to the bottom of the mattress). Perhaps a couple of straps can hold the bottom of the mattress tied to the base structure to avoid the vertical bouncing (something like SleepOne has in place on their bases)
4) The individual leg sections(of equal length) that make up the full leg could be made with different lengths and been provided with few extra sections of varying length so that the actual height of the base from the floor can be adjusted in smaller increments (instead of the current 3" length for each section)
There are some other minute improvement details although not worth mentioning.
But all in all, this base is well made, seems to use good parts (great 10-yr warranty), and is above average in design and performance. And if you factor in Sam's price? It is a steal !!!!!!