Perfect sound: it is just what is needed to realize that the machine works.
The mower works well but unfortunately is not incorporated in the razor. So we tend to overlook.
Finally, I like these cartridge cleaning systems. That leaves you always a pleasant scent on your shaving cheek and always smells good. (The hand washes are not always effective - sometimes we do a little faster, then shut the razor, and a musty odor escapes two days later.)
CHOOSE WHICH?
The 9000 series has 9 razors. The price of each model depends on the options present. Basically, we will be able to offer the best Philips shaver for 200 euros and 320 if you want fast Shaving option and the mower. The rest did not affect the quality of the shave, though it has obviously on convenience. But the first model is already an excellent choice!
To give you an idea of the choices, here is what I found using the manufacturer of the comparator:
Options (only the A and G options are directly affected shaving
A - Adjustment "Shaving soft, fast, ultra-fast"
B - Charge indicator 5 levels instead of 3
C - Charge indicator in%
D - Smartclean
E - More Smartclean (as Smartclean but dry more)
F - SmartClean Pro (as SmartClean Plus, but with digital display of progression)
G - beard Accessory (simulation 1-3 days) instead of precision trimmer (paws, contours)
Models - Price - Options
S9031 / 13 - 200 euros - No option.
S9021 / 13 - 230 euros - No options (white)
S9161 / 42-250 euros - G
S9031 / 27-280 euros - D
S9161 / 32 - 300 euros - E + G (silver)
S9111 - 300 euros - E + G (blue)
S9511 / 42-320 euros - A + B + G
S9521 / 32 - 370 euros - A + B + E + G
S9711 / 32 - 450 euros - A + C + F + G
This suggests that:
A + B = 70 euros
D = 50 euros
E = 50 euros
G = € 20
C + F = 80 euros more than B + E (!)