I visited showroom today for measuring drum size. Following is result, figures in inches.
Current LG Semi-Automatic > Height 14 and Diameter 16. So effective volume is 896*Pi
LG 6Kg Front Loader DD (best quote ₹30,500) > Depth 9 and Diameter 16. So volumes is 576 * Pi
Siemens 7Kg iQ300 (listed price ₹33,000) > Depth 11 and diameter 18 hence volume is 891 * Pi
Also I had noted listed price for LG T8067TEELR, 7Kg Top loader, last week which was ₹24,00. Today this model was not available on display. Hence I measured drum of 6.5Kg in same category which measures same as my current machine. Hence I can safely assume that 7Kg Top loader would be sufficient - drum size-wise. Hence if buying top loader, I will finalise on this one.
I would like to get opinion about Siemens model before jumping. LG 7Kg DD was almost ₹40,000, way out of my budget and was not available on display too.