Unfortunately I have never actually stepped foot into Mahal restaurant because they are my #1 takeaway curry house. I have driven by and the interiors (there are several Mahal's) seem to be clean and nice.
The curry selection is very good and includes many interesting regional selections that you don't typically see.
Try out the thali's and you will end up with enough food to feed an army. Highly recommend the Frankies as well - lamb wrapped in tortilla appetiser.