Bhai if u can get a terious kid ac (brand new) go for it. Sanden puts a lot of load on engine even in the factory fitted cars.
if ur ac guy is expert, then ask him to instal terious kid compressor which is i think is denso. Ask him to do few things:
do not instal the drier bottle inside engine room instead install the drier bottle in front part between the headlight so it will not get heated. Although u will have to bear extra cost for ac lines but it will give better cooling.
second get all the ac lines installed away from engine as much as possible, it will also effect cooling
third ask the guy to shut the exhaust portion under the dashobard so ur car inner coil doesnt get choked due to dust