i owned salmosa b4..now owning lachesis..
for salmosa
shape ok..if u are prefer ambiterous mouse
for performance..eh hem..sorry to say dat really nth more then any rojak brand except the higher dpi which reach 1800dpi

the prob of salmosa is the click..if say u playing fps game..the click touch is too light cant feel anything and the click easily spoiled..
since i plying cod and dota..so when click it wil got some weird sound feel lyk lack of lubricant

the for lachesis..i planing to sell it cos the shape not nice..it is unconfortable..for me the lachesis perform best in its programble key
the 2 button below the scroll is usually used for adjusting dpi..but i program it is numpad..and the left side 2 click also  used for same way..thats y i can program 4 short cut key on mouse..and its 3500dpi is more than enuf for any fps game..for personal opinion mamba 5600dpi is too extreme..cos seldom player wil use at dat high dpi

for myself..i prefer razer ambiterous mouse more than those ergonomic 1 cos razer ergonomic mouse not really fit most of player hand shape(i means among my fren) xcept mamba and da
but da and mamba r too thick..its horizontal movement is good enuf but not good in vertical movement.. so it only suitable for fps but not in strategy

sorry to say dat finally i conclude steelseries ikari laser(for high dpi user) and optical (for low dpi user) is best ergonomic gaming mouse

for ambiterous..lot razer mouse can performance well..i suggest any 1 razer which u like juz go ahead..cos for steel series xai..the only comment is expensive not really worth it xcept it fit ur hand very nicely..abyssus 3500dpi is more dan enuf

last 1 is question for razer
y u all design mamba and cr8 it
if i wrong plz correct me..is mamba totally same shape with DA..i think it only more programble button..when ply fps game need so many programable key??
on other hand, when u ply strategy game..the programable key really help lot..but as mention..mamba is not good in vertical movement if u all hold it using ur whole palm..if u only u use claw or fingertip the size is too big and its too thick..so i really don know it work best in which wise..

any way all above is personal opinion..(NO NEED THINK SO MUCH) go buy which u like and feel comfortable only lol